View source for Allies of World War II

{{Short description|Grouping of the victorious countries of the war}}
{{Redirect|Western Allies|the Cold War group|Western Bloc|the WWI group|Allies of World War I}}
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{{Use dmy dates|date=April 2021}}
{{Infobox geopolitical organization
| conventional_long_name = Allies of World War II
| common_name            = Allies
| native_name            = {{native name|zh|同盟國/同盟国}}<br>{{native name|fr|Alliés}}<br>{{native name|ru|Антигитлеровская коалиция|Antigitlerovskaya koalitsiya}}
| image_flag             = 
| image_flag2            = <!-- second flag -->
| image_map2             = United Nations "Fight For Freedom" poster.jpg
| status                 = [[Collective security#Collective defense|Military alliance]]
| year_end               = 1945
| life_span              = 1939–1945
| year_start             = 1939
| flag_alt               = <!-- alt text for flag -->
| flag_alt2              = <!-- alt text for second flag -->
| flag_type              = 
| image_map2_caption     = A 1943 poster showing the flags of many of the members of the Allies, including the "Big Three"
----
{{Plain list | style = padding-left: 0.6em; text-align: left; |
'''The Big Three:'''
* {{flagcountry|United Kingdom}} ([[United Kingdom declaration of war on Germany (1939)|from September 1939]])
* {{flagcountry|Soviet Union|1936}} ([[Operation Barbarossa|from June 1941]])
* {{flagcountry|United States|1912}} ([[Attack on Pearl Harbor|from December 1941]])
}}
[[#Summary table|Full list]]
| event_pre              = [[Franco-Polish alliance (1921)|Franco-Polish alliance]]
| date_pre               = {{nowrap|February 1921}}
| event_start            = [[Anglo-Polish military alliance|Anglo-Polish alliance]]
| date_start             = August
| event1                 = [[Anglo-French Supreme War Council|Anglo-French War Council]]
| date_event1            = {{nowrap|September 1939&nbsp;– June 1940}}
| event2                 = [[Declaration of St James's Palace|First Inter-Allied Meeting]]
| date_event2            = {{nowrap|June 1941}}
| event3                 = [[Anglo-Soviet Agreement|Anglo-Soviet alliance]]
| date_event3            = {{nowrap|July 1941}}
| event4                 = [[Atlantic Charter]]
| date_event4            = {{nowrap|August 1941}}
| event5                 = [[Declaration by United Nations]]
| date_event5            = {{nowrap|January 1942}}
| event6                 = [[Anglo-Soviet Treaty of 1942|Anglo-Soviet Treaty]]
| date_event6            = {{nowrap|May 1942}}
| event_end              = [[Potsdam Conference]]
| date_end               = July–August
| p1                     = 
| s1                     = United Nations
| flag_p1                = 
| flag_s1                = 
| flag_s2                = 
| s2                     = 
| image_s3               = 
| s3                     = 
| era                    = World War II
| event7                 = [[Tehran Conference]]
| date_event7            = {{nowrap|November–December 1943}}
| event8                 = {{nowrap|[[Bretton Woods Conference]]}}
| date_event8            = 1–15 July 1944
| event9                 = [[Yalta Conference]]
| date_event9            = 4–11 February 1945
| event10                = [[United Nations Conference on International Organization|United Nations formed]]
| date_event10           = {{nowrap|April–June 1945}}
| flag                   = <!-- link target under flag image. Default: Flag of {{{common_name}}} -->
| flag2                  = <!-- link target under flag2 image. Default: Flag of {{{common_name}}} -->
| flag2_type             = 
}}
[[File:Teheran conference-1943.jpg|thumb|alt=Three men, Stalin, Roosevelt and Churchill, sitting together elbow to elbow|The Allied leaders of the [[European theatre of World War II|European theatre]] (left to right): [[Joseph Stalin]], [[Franklin D. Roosevelt]] and [[Winston Churchill]] meeting at the [[Tehran Conference]] in 1943]]
[[File:Cairo conference.jpg|thumb|alt=Three men, Chiang Kai-shek, Roosevelt and Churchill, sitting together elbow to elbow|The Allied leaders of the [[Pacific War|Asian and Pacific Theater]]: Generalissimo [[Chiang Kai-shek]], [[Franklin D. Roosevelt]], and [[Winston Churchill]] meeting at the [[Cairo Conference (1943)|Cairo Conference]] in 1943]]
[[File:M Touissant Pologne France Angleterre.jpg|thumb|French postcard illustrating the alliance between Poland, France and the United Kingdom (1939)]]
[[File:Stamp of USSR 0878.jpg|thumb|"Long live the victory of the Anglo-Soviet-American military alliance!" – USSR stamp of 1943, quoting Stalin]]

The '''Allies''', formally referred to as the '''United Nations''' from 1942, were an international [[Coalition#Military|military coalition]] formed during [[World War II]] (1939–1945) to oppose the [[Axis powers]]. Its principal members by the end of 1941 were the "[[Four Policemen|Big Four]]" – the [[United Kingdom]], [[United States]], [[Soviet Union]], and [[Republic of China (1912–1949)|China]].

Membership in the Allies varied during the course of the war. When the conflict broke out on 1 September 1939, the Allied coalition consisted of the United Kingdom, [[French Third Republic|France]], and [[Second Polish Republic|Poland]], as well as their respective [[Dependent territory|dependencies]], such as [[British Raj|British India]]. They were joined by the independent [[dominion]]s of the [[British Commonwealth]]: [[Canada]], [[Australia]], [[Dominion of New Zealand|New Zealand]] and [[Union of South Africa|South Africa]]. Consequently, the initial alliance resembled [[Allies of World War I|that of the First World War]]. As Axis forces began [[German invasion of the Netherlands|invading northern Europe]] and the [[Balkans campaign (World War II)|Balkans]], the Allies added the [[Netherlands]], [[Belgium]], [[Norway]], [[Kingdom of Greece|Greece]], and [[Kingdom of Yugoslavia|Yugoslavia]]. The Soviet Union, which initially had a [[Molotov–Ribbentrop Pact|nonaggression pact]] with Germany and participated in its [[Soviet invasion of Poland|invasion of Poland]], joined the Allies after the [[German invasion of the Soviet Union]] in June 1941.<ref>{{Cite web|url=https://history.state.gov/milestones/1937-1945/us-soviet|title=Milestones: 1937–1945 |publisher=Office of the Historian |url-status=live |archive-url= https://web.archive.org/web/20230922040307/https://history.state.gov/milestones/1937-1945/us-soviet |archive-date= Sep 22, 2023 }}</ref>{{Failed verification|date=July 2023}} The United States, while providing some [[materiel]] support to European Allies since September 1940, remained formally neutral until the Japanese [[attack on Pearl Harbor]] in December 1941, after which it [[Consequences of the attack on Pearl Harbor|declared war and officially joined]] the Allies. China had already been [[Second Sino-Japanese War|at war]] with Japan [[Marco Polo Bridge Incident|since 1937]], and formally joined the Allies in December 1941.

The Allies were led by the so-called "Big Three"—the United Kingdom, the Soviet Union, and the United States—which were the principal contributors of manpower, resources, and strategy, each playing a key role in achieving victory.<ref name=":7">{{Cite book |last=Johnsen|first=William T.|url=https://books.google.com/books?id=ivm6DAAAQBAJ|title=The Origins of the Grand Alliance: Anglo-American Military Collaboration from the Panay Incident to Pearl Harbor |date=2016 |publisher=University Press of Kentucky|isbn=978-0-8131-6836-4|language=en|quote=Although many factors manifestly contributed to the ultimately victory, not least the Soviet Union's joining of the coalition, the coalition partners' ability to orchestrate their efforts and coordinate the many elements of modern warfare successfully must rank high in any assessment.}}</ref><ref name=":3" /><ref name=":8">{{Cite book|last1=Lane|first1=Ann|url=https://books.google.com/books?id=5T2wCwAAQBAJ|title=The Rise and Fall of the Grand Alliance, 1941–45|last2=Temperley|first2=Howard|date=1996|publisher=Springer|isbn=978-1-349-24242-9 |language=en |quote=This collection by leading British and American scholars on twentieth century international history covers the strategy, diplomacy and intelligence of the Anglo-American-Soviet alliance during the Second World War. It includes the evolution of allied war aims in both the European and Pacific theatres, the policies surrounding the development and use of the atomic bomb and the evolution of the international intelligence community.}}</ref> A series of conferences between Allied leaders, diplomats, and military officials gradually shaped the makeup of the alliance, the direction of the war, and ultimately the postwar international order. Relations between the United Kingdom and the United States were [[Special Relationship|especially close]], with their bilateral [[Atlantic Charter]] forming the groundwork of their alliance.

The Allies became a formalized group upon the [[Declaration by United Nations]] on 1 January 1942, which was signed by 26 nations around the world; these ranged from [[List of governments in exile during World War II|governments in exile]] from the Axis occupation to small nations far removed from the war. The Declaration officially recognized the Big Three and China as the "Four Powers",<ref>Hoopes, Townsend, and Douglas Brinkley. ''FDR and the Creation of the U.N.'' (Yale University Press, 1997).</ref> acknowledging their central role in prosecuting the war; they were also referred to as the "[[trustee]]ship of the powerful", and later as the "[[Four Policemen]]" of the United Nations.<ref name="Justus">{{cite book |last1=Doenecke |first1=Justus D. |last2=Stoler |first2=Mark A. |title=Debating Franklin D. Roosevelt's Foreign Policies, 1933–1945 |url=https://books.google.com/books?id=xdMF9rX6mX8C&pg=PA62 |year=2005 |publisher=Rowman & Littlefield |isbn=978-0847694167 }}</ref> Many more countries joined through to the final days of the war, including colonies and former Axis nations. After the war ended, the Allies, and the Declaration that bound them, would become the basis of the modern [[United Nations]];<ref>Ian C. B. Dear and Michael Foot, eds. ''The Oxford Companion to World War II'' (2005), pp. 29, 1176</ref> one enduring legacy of the alliance is the [[permanent members of the United Nations Security Council|permanent membership of the U.N. Security Council]], which is made up exclusively of the principal Allied powers that won the war.
{{TOC limit|4}}

==Origins==
{{Main|Causes of World War II}}

The victorious [[Allies of World War I]]—which included what would become the Allied powers of the Second World War—had imposed harsh terms on the opposing [[Central Powers]] in the [[Paris Peace Conference (1919–1920)|Paris Peace Conference of 1919–1920]]. [[German Empire|Germany]] resented signing the [[Treaty of Versailles]], which required that it take full responsibility for the war, lose a significant portion of territory, and pay costly reparations, among other penalties. The [[Weimar Republic]], which formed at the end of the war and subsequently negotiated the treaty, saw its legitimacy shaken, particularly as it struggled to govern a greatly weakened economy and humiliated populace.

The [[Wall Street Crash of 1929]], and the ensuing [[Great Depression]], led to political unrest across Europe, especially in Germany, where [[Revanchism|revanchist]] nationalists blamed the severity of the economic crisis on the Treaty of Versailles. The far-right [[Nazi Party]] led by [[Adolf Hitler]], which had formed shortly after the peace treaty, exploited growing popular resentment and desperation to become the dominant political movement in Germany. By 1933, they [[Adolf Hitler's rise to power|gained power]] and rapidly established a [[Totalitarianism|totalitarian]] regime known as [[Nazi Germany]]. The Nazi regime demanded the immediate cancellation of the Treaty of Versailles and made claims over German-populated Austria and the [[Sudetenland|German-populated territories]] of Czechoslovakia. The likelihood of war was high, but none of the major powers had the appetite for another conflict; many governments sought to ease tensions through nonmilitary strategies such as [[appeasement]].

Japan, which was a principal allied power in the First World War, had since become increasingly militaristic and imperialistic; parallel to Germany, nationalist sentiment increased throughout the 1920s, culminating in the [[Japanese invasion of Manchuria|invasion of Manchuria]] in 1931. The [[League of Nations]] strongly condemned the attack as an act of aggression against China; Japan responded by leaving the League in 1933. The second [[Second Sino-Japanese War|Sino-Japanese War]] erupted in 1937 with Japan's full-scale invasion of China. The League of Nations condemned Japan's actions and initiated sanctions; the United States, which had attempted to peacefully negotiate for peace in Asia, was especially angered by the invasion and sought to support China.

{{multiple image
 | caption_align = center
| align = right
| direction = horizontal
| header =
| header_align = left/right/center
| footer =
| footer_align = left
| image1 = Poland First To Fight.jpg
| width1 = 150
| caption1 = British wartime poster supporting Poland after the [[Invasion of Poland|German invasion of the country]] ([[European theatre of World War II|European theater]])
| image2 = "China-First to Fight - NARA - 513567.jpg
| width2 = 150
| caption2 = American wartime poster promoting aid to China during the [[Second Sino-Japanese War]] ([[Pacific Ocean theater of World War II|Pacific theater]])
}}
In March 1939, [[German occupation of Czechoslovakia|Germany took over Czechoslovakia]], just six months after signing the [[Munich Agreement]], which sought to appease Hitler by [[German occupation of Czechoslovakia|ceding]] the [[Sudeten Germans|mainly ethnic German]] Czechoslovak borderlands; while most of Europe had celebrated the agreement as a major victory for peace, the open flaunting of its terms demonstrated the failure of appeasement. Britain and France, which had been the main advocates of appeasement, decided that Hitler had no intention to uphold diplomatic agreements and responded by preparing for war. On 31 March 1939, Britain formed the [[Anglo-Polish military alliance]] in an effort to avert an imminent German attack on Poland; the French likewise had a long-standing [[Franco-Polish alliance (1921)|alliance with Poland since 1921]].

The [[Soviet Union]], which had been diplomatically and economically isolated by much of the world, had sought an alliance with the western powers, but Hitler preempted a potential war with Stalin by signing the [[Molotov–Ribbentrop Pact|Nazi–Soviet non-aggression pact]] in August 1939. In addition to preventing a two-front war that had battered its forces in the last world war, the agreement secretly divided the independent states of Central and Eastern Europe between the two powers and assured adequate oil supplies for the German war machine.

On 1 September 1939, [[Invasion of Poland|Germany invaded Poland]]; two days later Britain and France declared war on Germany. Roughly two weeks after Germany's attack, the [[Soviet invasion of Poland|Soviet Union invaded Poland]] from the east. Britain and France established the [[Anglo-French Supreme War Council]] to coordinate military decisions. A [[Polish government-in-exile]] was set up in London, joined by hundreds of thousands of Polish soldiers, which would remain an Allied nation until the end. After a quiet winter, Germany began its invasion of Western Europe in April 1940, quickly defeating Denmark, Norway, Belgium, the Netherlands, and France. All the occupied nations subsequently established a government-in-exile in London, with each contributing a contingent of escaped troops. Nevertheless, by roughly one year since Germany's violation of the Munich Agreement, Britain and its Empire stood alone against Hitler and Mussolini.

== Formation of the "Grand Alliance" {{anchor|Grand Alliance}} ==
{{Further|Diplomatic history of World War II}}
Before they were formally allied, the United Kingdom and the United States had cooperated in a number of ways,<ref name=":7" /> notably through the [[destroyers-for-bases deal]] in September 1940 and the American [[Lend-Lease]] program, which provided Britain and the Soviet Union with war materiel beginning in October 1941.<ref>{{Cite web|title=How Much of What Goods Have We Sent to Which Allies? |url=https://www.historians.org/about-aha-and-membership/aha-history-and-archives/gi-roundtable-series/pamphlets/em-13-how-shall-lend-lease-accounts-be-settled-(1945)/how-much-of-what-goods-have-we-sent-to-which-allies|access-date=2021-09-01|publisher=American Historical Association}}</ref><ref>{{Cite web|title=Milestones: 1937–1945 |publisher=Office of the Historian, Department of State|url=https://history.state.gov/milestones/1937-1945/lend-lease|access-date=2021-08-23|location=United States}}</ref> The [[British Commonwealth]] and, to a lesser extent, the Soviet Union reciprocated with a smaller [[Lend-Lease#Reverse Lend-Lease|Reverse Lend-Lease]] program.<ref>{{Cite journal|last=E.|first=D. P.|date=1945|title=Lend-Lease and Reverse Lend-Lease Aid: Part II|url=https://www.jstor.org/stable/25643770|journal=Bulletin of International News|volume=22|issue=4|pages=157–164|jstor=25643770|issn=2044-3986}}</ref><ref>{{Cite web|title=How Much Help Do We Get Via Reverse Lend-Lease? |url=https://www.historians.org/about-aha-and-membership/aha-history-and-archives/gi-roundtable-series/pamphlets/em-13-how-shall-lend-lease-accounts-be-settled-(1945)/how-much-help-do-we-get-via-reverse-lend-lease|access-date=2021-09-01|publisher=American Historical Association}}</ref>

The [[Declaration of St James's Palace|First Inter-Allied Meeting]] took place in London in early June 1941 between the United Kingdom, the four co-belligerent British Dominions (Canada, Australia, New Zealand and South Africa), the eight [[List of governments in exile during World War II|governments in exile]] ([[Belgian government in exile|Belgium]], [[Czechoslovak government-in-exile|Czechoslovakia]], [[Greek government-in-exile|Greece]], [[Luxembourg government in exile|Luxembourg]], [[Dutch government-in-exile|the Netherlands]], [[Nygaardsvold's Cabinet|Norway]], [[Polish government-in-exile|Poland]], [[Yugoslav government-in-exile|Yugoslavia]]) and [[Free France]]. The meeting culminated with the [[Declaration of St James's Palace]], which set out a first vision for the postwar world.

In June 1941, Hitler broke the non-aggression agreement with Stalin and Axis forces [[Operation Barbarossa|invaded the Soviet Union]], which consequently declared war on Germany and its allies. Britain agreed to an [[Anglo-Soviet Agreement|alliance with the Soviet Union]] in July, with both nations committing to assisting one another by any means, and to never negotiate a separate peace.<ref>{{Cite book |last=Weinberg |first=Gerhard L. |title=A World at Arms: a global history of World War II |publisher=Cambridge University Press |year=2005 |isbn=978-0521853163 |edition=2nd |pages=284–285 |quote=On the political front, the Soviet Union and Great Britain had signed an agreement in Moscow on July 12, 1941. Requested by Stalin as a sign of cooperation, it provided for mutual assistance and an understanding not to negotiate or conclude an armistice or peace except by mutual consent. Soviet insistence on such an agreement presumably reflected their suspicion of Great Britain, though there is no evidence that either party to it ever ceased to have its doubt about the loyalty of the other if attractive alternatives were thought to be available.}}</ref> The following August saw the [[Atlantic Conference]] between American President [[Franklin D. Roosevelt|Franklin Roosevelt]] and British Prime Minister [[Winston Churchill]], which defined a common Anglo-American vision of the postwar world, as formalized by the [[Atlantic Charter]].<ref>{{Cite book|last=Ninkovich|first=Frank|title=The Wilsonian Century: US Foreign Policy since 1900|publisher=Chicago University Press|year=1999|location=Chicago|page=131}}</ref>

At the [[Atlantic Charter#Acceptance by Inter-Allied Council and United Nations|Second Inter-Allied Meeting]] in London in September 1941, the eight European governments in exile, together with the Soviet Union and representatives of the Free French Forces, unanimously adopted adherence to the common principles of policy set forth in the Atlantic Charter. In December, Japan attacked American and British territories in Asia and the Pacific, resulting in the U.S. formally entering the war as an Allied power. Still reeling from Japanese aggression, China declared war on all the Axis powers shortly thereafter.

By the end of 1941, the main lines of World War II had formed. Churchill referred to the "Grand Alliance" of the United Kingdom, the United States, and the Soviet Union,<ref name=":5">{{Cite book|last=Churchill|first=Winston S.|url=https://books.google.com/books?id=8NVN-pyIDzgC|title=The Grand Alliance|date=1950|publisher=Houghton Mifflin|language=en}}</ref><ref name=":9">{{Cite web|title=The state of the world after World War Two and before the Cold War – The Cold War origins, 1941–1948 |url=https://www.bbc.co.uk/bitesize/guides/zt8ncwx/revision/1|access-date=4 April 2021|website=BBC Bitesize|language=en-GB|quote=The USA entered World War Two against Germany and Japan in 1941, creating the Grand Alliance of the USA, Britain and the USSR. This alliance brought together great powers that had fundamentally different views of the world, but they did co-operate for four years against the Germans and Japanese. The Grand Alliance would ultimately fail and break down into the Cold War.}}</ref> which together played the largest role in prosecuting the war. The alliance was largely one of convenience for each member: the U.K. realized that the Axis powers threatened not only [[British Empire|its colonies]] in North Africa and Asia but also the [[Great Britain|homeland]]. The United States felt that the Japanese and German expansion should be contained, but ruled out force until Japan's attack. The Soviet Union, having been betrayed by [[Operation Barbarossa|the Axis attack]] in 1941, greatly despised German belligerence and the unchallenged Japanese expansion in the East, particularly considering their defeat in previous wars with Japan; the Soviets also recognized, as the U.S. and Britain had suggested, the advantages of a [[two-front war]].

=== The Big Three ===
[[File:The Queen and Princess Elizabeth talk to paratroopers in front of a Halifax aircraft during a tour of airborne forces preparing for D-Day, 19 May 1944. H38612.jpg|thumb|[[Queen Elizabeth The Queen Mother|Queen Elizabeth]] and [[Elizabeth II|Princess Elizabeth]] talking to paratroopers in preparation of [[Normandy landings|D-Day]], 19 May 1944]]
[[File:World-War-II-military-deaths-in-Europe-by-theater-year.png|thumb|[[World War II casualties|World War II military deaths]] in Europe and military situation in autumn 1944]]
[[Franklin D. Roosevelt]], [[Winston Churchill]], and [[Joseph Stalin]] were The Big Three leaders. They were in frequent contact through ambassadors, top generals, foreign ministers and special emissaries such as the American [[Harry Hopkins]]. It is also often called the "Strange Alliance", because it united the leaders of the world's greatest [[capitalist state]] (the United States), the greatest [[socialist state]] (the Soviet Union) and the greatest [[Colonialism|colonial power]] (the United Kingdom).<ref name="Ambrose">{{cite book|last = Ambrose | first = Stephen | author-link = Stephen Ambrose | title = Rise to Globalism: American Foreign Policy Since 1938 | publisher = [[Penguin Books]]| year = 1993 | location = New York | page = 15 }}</ref>

Relations between them resulted in the major decisions that shaped the war effort and planned for the postwar world.<ref name=":8" /><ref>{{cite book|last=Sainsbury|first=Keith|title=The Turning Point: Roosevelt, Stalin, Churchill, and Chiang Kai-Shek, 1943: The Moscow, Cairo, and Teheran Conferences|publisher=[[Oxford University Press]]|year=1986|location=[[Oxford]]}}</ref> Cooperation between the United Kingdom and the United States was [[Special Relationship|especially close]] and included forming a [[Combined Chiefs of Staff]].<ref name=":6">{{Cite book|last=Stoler|first=Mark A.|url=https://books.google.com/books?id=gvTGDwAAQBAJ|title=Allies and Adversaries: The Joint Chiefs of Staff, the Grand Alliance, and U.S. Strategy in World War II|date=2004|publisher=UNC Press Books|isbn=978-0-8078-6230-8|language=en|quote=merging of their chiefs of staff organizations into the Combined Chiefs of Staff (CCS) to direct their combined forces and plan global strategy. ... the strategic, diplomatic, security, and civil-military views of the service chiefs and their planners were based to a large extent on events that had taken place before December 7, 1941}}</ref>

There were numerous [[List of Allied World War II conferences|high-level conferences]]; in total Churchill attended 14 meetings, Roosevelt 12, and Stalin 5. Most visible were the three summit conferences that brought together the three top leaders.<ref>Herbert Feis, ''Churchill Roosevelt Stalin: The War They Waged and the Peace They Sought: A Diplomatic History of World War II'' (1957)</ref><ref>William Hardy McNeill, ''America, Britain and Russia: their co-operation and conflict, 1941–1946'' (1953)</ref> The Allied policy toward Germany and Japan evolved and developed at these three conferences.<ref>{{Citation|last=Wolfe|first=James H.|title=The Diplomacy of World War II Genesis of the Problem|date=1963|url=https://doi.org/10.1007/978-94-011-9199-9_2|work=Indivisible Germany: Illusion or Reality?|pages=3–28|editor-last=Wolfe|editor-first=James H.|place=Dordrecht|publisher=Springer Netherlands|language=en|doi=10.1007/978-94-011-9199-9_2|isbn=978-94-011-9199-9|access-date=22 November 2020}}</ref>
* [[Tehran Conference]] (codename "Eureka") – first meeting of The Big Three (28 November 1943 [[Molotov–Ribbentrop Pact|–]] 1 December 1943)
* [[Yalta Conference]] (codename "Argonaut") – second meeting of The Big Three (4–11 February 1945)
* [[Potsdam Conference]] (codename "Terminal") – third and final meeting of The Big Three (Truman having taken over for Roosevelt, 17 July – 2 August 1945)

===Tensions===
There were many tensions among the Big Three leaders, although they were not enough to break the alliance during wartime.<ref name=":3">{{Cite web|title=The Big Three|url=https://www.nationalww2museum.org/war/articles/big-three|access-date=4 April 2021|website=The National WWII Museum New Orleans|language=en|quote=In World War II, the three great Allied powers—Great Britain, the United States, and the Soviet Union—formed a Grand Alliance that was the key to victory. But the alliance partners did not share common political aims, and did not always agree on how the war should be fought.}}</ref><ref name=":4">{{Cite web|last=Roos|first=Dave|title=FDR, Churchill and Stalin: Inside Their Uneasy WWII Alliance|url=https://www.history.com/news/big-three-allies-wwii-roosevelt-churchill-stalin|access-date=4 April 2021|website=History.com|date=12 June 2020 |language=en|quote=There were bright hopes that the cooperative spirit of the Grand Alliance would persist after WWII, but with FDR's death only two months after Yalta, the political dynamics changed dramatically.}}</ref>

In 1942 Roosevelt proposed becoming, with China, the [[Four Policemen]] of world peace. Although the 'Four Powers' were reflected in the wording of the [[Declaration by United Nations]], Roosevelt's proposal was not initially supported by Churchill or Stalin.

Division emerged over the length of time taken by the Western Allies to establish a [[Western Front (World War II)|second front]] in Europe.<ref name="Jones" /> Stalin and the Soviets used the potential employment of the second front as an 'acid test' for their relations with the Anglo-American powers.<ref name=":0">{{Cite book|title=The United States and the Origins of the Cold War, 1941–1947|last=Gaddis|first=John Lewis|year=2000|location=New York|pages=65}}</ref> The Soviets were forced to use as much manpower as possible in the fight against the Germans, whereas the United States had the luxury of flexing industrial power, but with the "minimum possible expenditure of American lives".<ref name=":0" /> Roosevelt and Churchill opened ground fronts in North Africa in 1942 and in Italy in 1943, and launched a massive air attack on Germany, but Stalin kept wanting more.

Although the U.S. had a strained relationship with the USSR in the 1920s, relations were normalized in 1933. The original terms of the [[Lend-Lease]] loan were amended towards the Soviets, to be put in line with British terms. The United States would now expect interest with the repayment from the Soviets, following the initiation of the [[Operation Barbarossa]], at the end of the war—the United States were not looking to support any "postwar Soviet reconstruction efforts",<ref>{{Cite book|title=The United States and the Origins of the Cold War, 1941–1947|last=Gaddis|first=John Lewis|year=2000|location=New York|pages=178–179}}</ref> which eventually manifested into the [[Molotov Plan]]. At the [[Tehran Conference|Tehran conference]], Stalin judged Roosevelt to be a "lightweight compared to the more formidable Churchill".<ref>{{Cite book|last=Groom|first=Winston|url=https://books.google.com/books?id=AWhPDwAAQBAJ&q=allied+leaders+of+world+war+II+big+three&pg=PT13|title=The Allies: Roosevelt, Churchill, Stalin, and the Unlikely Alliance That Won World War II|date=2018|publisher=National Geographic|isbn=978-1-4262-1986-3|language=en|quote=After a long chat, Stalin went away amused by the American president's cheery, casual approach to diplomacy but judged him a lightweight compared to the more formidable Churchill}}</ref><ref>{{Cite web|date=2019-01-11|title=The inside story of how Roosevelt, Churchill, and Stalin won World War II|url=https://www.nationalgeographic.com/culture/article/allies-roosevelt-churchill-stalin-won-world-war-II|archive-url=https://web.archive.org/web/20210228225217/https://www.nationalgeographic.com/culture/article/allies-roosevelt-churchill-stalin-won-world-war-II|url-status=dead|archive-date=28 February 2021|access-date=2021-04-06|website=Culture|language=en|quote= Groom describes how 'fake news' about the Soviet Union blinded Roosevelt to Stalin's character and intentions&nbsp;... Churchill [had] been on to Stalin from the beginning and he did not trust the Communists at their word. Roosevelt was more ambivalent.}}</ref> During the meetings from 1943 to 1945, there were disputes over the growing list of demands from the USSR.

Tensions increased further when Roosevelt died and his successor [[Harry Truman]] rejected demands put forth by Stalin.<ref name="Jones">{{cite book|last = Jones | first = Maldwyn | author-link = Maldwyn Jones | title = The Limits of Liberty: American History 1607–1980 | publisher = [[Oxford University Press]]| year = 1983 | location = Oxford | page = 505}}</ref> Roosevelt wanted to play down these ideological tensions.<ref>{{Cite journal|last=Costigliola|first=Frank|date=2010|title=After Roosevelt's Death: Dangerous Emotions, Divisive Discourses and the Abandoned Alliance|journal=Diplomatic History|volume=34|issue=1|page=19|doi=10.1111/j.1467-7709.2009.00830.x|doi-access=free|issn = 0145-2096}}</ref> Roosevelt felt he "understood Stalin's psychology", stating "Stalin was too anxious to prove a point&nbsp;... he suffered from an inferiority complex."<ref>{{Cite journal|last=Costigliola|first=Frank|date=2010|title=After Roosevelt's Death: Dangerous Emotions, Divisive Discourses and the Abandoned Alliance|journal=Diplomatic History|volume=34|issue=1|pages=7–8|doi=10.1111/j.1467-7709.2009.00830.x|doi-access=free}}</ref>

==United Nations==
[[File:United Nations Fight for Freedom poster.jpg|thumb|upright|Wartime poster for the [[Declaration by United Nations|United Nations]], created in 1941 by the [[United States Office of War Information|U.S. Office of War Information]]]]

=== Four Policemen ===
{{Main|Four Policemen}}

During December 1941, Roosevelt devised the name "United Nations" for the Allies and Churchill agreed.<ref name=":1">{{cite book|last1=Ward|first1=Geoffrey C.|title=The Roosevelts: An Intimate History|last2=Burns|first2=Ken|date=2014|publisher=Knopf Doubleday Publishing Group|isbn=978-0385353069|chapter=Nothing to Conceal|chapter-url=https://books.google.com/books?id=V73CAwAAQBAJ&pg=SA6-PA60}}</ref><ref name=":2">{{cite web|date=3 February 2007|title=United Nations|url=http://www.wordorigins.org/index.php/site/comments/united_nations/|url-status=dead|archive-url=https://web.archive.org/web/20160331193323/http://www.wordorigins.org/index.php/site/comments/united_nations/|archive-date=31 March 2016|access-date=28 March 2016|website=Wordorigins.org}}</ref> He referred to the Big Three and China as the "[[Four Policemen]]" repeatedly from 1942.<ref>Richard W. Van Alstyne, "The United States and Russia in World War II: Part I" ''Current History'' 19#111 (1950), pp. 257–260 [https://www.jstor.org/stable/45307844 online]</ref>

=== Declaration by United Nations ===
{{Main|Declaration by United Nations}}

The alliance was formalised in the [[Declaration by United Nations]] signed on 1 January 1942. There were the 26 original signatories of the declaration; the Big Four were listed first:<!-- NOTE: The following names are as stated on the Declaration; please do not change them. -->

{{Div col|colwidth=15em}}
* {{flagicon|United States|1912}} [[United States]]
* {{flagicon|United Kingdom}} [[United Kingdom]]
* {{flagicon|Soviet Union|1936}} [[Soviet Union]]
* {{flagicon|Republic of China (1912–1949)}} [[Republic of China (1912–1949)|China]]
* {{flagicon|Australia}} [[Australia]]
* {{flagicon|Belgium}} [[Belgium]]
* {{flagicon|Canada|1921}} [[Canada]]
* {{flagicon|Costa Rica}} [[Costa Rica]]
* {{flagicon|Cuba|1902}} [[Republic of Cuba (1902–1959)|Cuba]]
* {{flagicon|Czech Republic}} [[Czechoslovakia]]
* {{flagicon|Dominican Republic}} [[Third Republic (Dominican Republic)|Dominican Republic]]
* {{flagicon|El Salvador}} [[El Salvador]]
* {{flagicon|Kingdom of Greece|state}} [[Kingdom of Greece|Greece]]
* {{flagicon|Guatemala}} [[Guatemala]]
* {{flagicon|Haiti|1859}} [[Republic of Haiti (1859–1957)|Haiti]]
* {{flagicon|Honduras|1866}} [[Honduras]]
* {{flagicon|British Raj}} [[British Raj|British India]]
* {{flagicon|Luxembourg}} [[Luxembourg]]
* {{flagicon|Netherlands}} [[Netherlands]]
* {{flagicon|Dominion of New Zealand}} [[Dominion of New Zealand|New Zealand]]
* {{flagicon|Nicaragua|1908}} [[Nicaragua]]
* {{flagicon|Norway}} [[Norway]]
* {{flagicon|Panama}} [[Panama]]
* {{flagicon|Second Polish Republic}} [[Second Polish Republic|Poland]]
* {{flagicon|Union of South Africa}} [[Union of South Africa|South Africa]]
* {{flagicon|Kingdom of Yugoslavia}} [[Kingdom of Yugoslavia|Yugoslavia]]
{{colend}}

===Alliance growing===

The United Nations began growing immediately after its formation. In 1942, Mexico, the Philippines and Ethiopia adhered to the declaration. Ethiopia had been restored to independence by British forces after the Italian defeat in 1941. The Philippines, still owned by Washington but granted international diplomatic recognition, was allowed to join on 10 June despite its occupation by Japan.

In 1943, the Declaration was signed by Iraq, Iran, Brazil, Bolivia and Colombia. [[Anglo-Soviet invasion of Iran#Occuption|A Tripartite Treaty of Alliance]] with Britain and the USSR formalised Iran's assistance to the Allies.<ref>{{cite book|last=Motter|first=T.H. Vail|url=http://www.history.army.mil/books/wwii/persian/index.htm#contents|title=The Persion Corridor and Aid to Russia|publisher=[[United States Army Center of Military History]]|year=2000|series=United States Army in World War II|chapter=Chapter I: Experiment in Co-operation|id=CMH Pub 8-1|access-date=15 May 2010|orig-year=1952|chapter-url=http://www.history.army.mil/books/wwii/persian/chapter01.htm#b2|archive-url=https://web.archive.org/web/20100505141525/http://www.history.army.mil/books/wwii/persian/index.htm|archive-date=5 May 2010|url-status=live}}</ref> In [[Rio de Janeiro]], Brazilian dictator [[Getúlio Vargas]] was considered near to fascist ideas, but realistically joined the United Nations after their evident successes.{{citation needed|date=April 2023}}

In 1944, Liberia and France signed. The French situation was very confused. [[Free France|Free French]] forces were recognized only by Britain, while the United States considered [[Vichy France]] to be the legal government of the country until [[Operation Overlord]], while also preparing [[AM-Franc|U.S. occupation francs]]. Winston Churchill urged Roosevelt to restore France to its status of a major power after the liberation of Paris in August 1944; the Prime Minister feared that after the war, Britain could remain the sole great power in Europe facing the Communist threat, as it was in 1940 and 1941 against Nazism.

During the early part of 1945, Peru, Chile, Paraguay, Venezuela, Uruguay, Turkey, Egypt, Saudi Arabia, Lebanon, Syria (these latter two French colonies had been declared independent states by British occupation troops, despite protests by Pétain and later De Gaulle) and Ecuador became signatories. [[Ukrainian Soviet Socialist Republic|Ukraine]] and [[Byelorussian Soviet Socialist Republic|Belarus]], which were not independent states but parts of the Soviet Union, were accepted as members of the United Nations as a way to provide greater influence to Stalin, who had only Yugoslavia as a communist partner in the alliance.

==Major Allied states==
{{see also|Diplomatic history of World War II}}

{{multiple image
| align = right
| total_width = 400
| image1 = FDR 1944 Color Portrait.jpg
| width1 = 300
| height1 = 350
| image2 = Winston Churchill.jpg
| width2 = 300
| height2 = 400
| image3 = Stalin Museum Batumi.jpg
| width3 = 300
| height3 = 350
| image4 = Chiang Kai-shek enhanced.jpg
| width4 = 300
| height4 = 400
| image5 = General Charles de Gaulle in 1945 (cropped).jpg
| width5 = 300
| height5 = 350
| footer = [[Franklin Roosevelt]], [[Winston Churchill]], [[Joseph Stalin]], [[Chiang Kai-shek]] and [[Charles de Gaulle]] were leaders of the [[Permanent members of the United Nations Security Council|Big Five]]
}}

=== United Kingdom ===
{{Further|Military history of the United Kingdom during World War II|British Empire in World War II}}
[[File:Spitfire and He 111 during Battle of Britain 1940.jpg|thumb|British [[Supermarine Spitfire]] fighter aircraft (bottom) flying past a German [[Heinkel He 111]] bomber aircraft (top) during the [[Battle of Britain]] in 1940]]
[[File:IWM-E-6724-Crusader-19411126.jpg|thumb|British [[Crusader tank]]s during the [[North African Campaign]]]]
[[File:HMS Ark Royal attack.jpg|thumb|British aircraft carrier {{HMS|Ark Royal|91|6}} under attack from Italian aircraft during the [[Battle of Cape Spartivento]] (27 November 1940)]]
[[File:The British Army in North-west Europe 1944-45 B15008.jpg|thumb|British soldiers of the [[King's Own Yorkshire Light Infantry]] in [[Elst, Gelderland|Elst]], Netherlands on 2 March 1945]]

British Prime Minister, [[Neville Chamberlain]] delivered his ''Ultimatum Speech'' on 3 September 1939 which [[United Kingdom declaration of war on Germany (1939)|declared war on Germany]], a few hours before France. As the [[Statute of Westminster 1931]] was not yet ratified by the parliaments of Australia and New Zealand, the British declaration of war on Germany also applied to those [[dominion]]s. The other dominions and members of the [[Commonwealth of Nations|British Commonwealth]] declared war from 3 September 1939, all within one week of each other; they were [[Canada]], [[British Raj|British India]] and [[Union of South Africa|South Africa]].<ref>Davies 2006, pp 150–151.</ref>

During the war, Churchill attended seventeen [[List of Allied World War II conferences|Allied conferences]] at which key decisions and agreements were made. He was "the most important of the Allied leaders during the first half of World War II".<ref>{{Cite book|last=Taylor|first=Mike|url=https://books.google.com/books?id=p4R6AgAAQBAJ&pg=PA13|title=Leaders of World War II|date=2010|publisher=ABDO|isbn=978-1-61787-205-1|location=|pages=|language=en}}</ref>

====African colonies and dependencies====
{{Further|Southern Rhodesia in World War II}}

[[British West Africa]] and the British colonies in East and Southern Africa participated, mainly in the North African, East African and Middle-Eastern theatres. Two West African and one East African division served in the [[Burma Campaign]].

[[Southern Rhodesia]] was a self-governing colony, having received [[responsible government]] in 1923. It was not a sovereign dominion. It governed itself internally and controlled its own armed forces, but had no diplomatic autonomy, and, therefore, was officially at war as soon as Britain was at war. The Southern Rhodesian colonial government issued a symbolic declaration of war nevertheless on 3 September 1939, which made no difference diplomatically but preceded the declarations of war made by all other British dominions and colonies.<ref>{{cite book|title=So Far And No Further! Rhodesia's Bid For Independence During the Retreat From Empire 1959–1965|last=Wood|first=J R T|date=2005|location=Victoria, British Columbia|publisher=[[Trafford Publishing]]|isbn= 978-1-4120-4952-8|pages=8–9}}</ref>

====American colonies and dependencies====

These included: the [[British West Indies]], [[British Honduras]], [[British Guiana]] and the [[Falkland Islands]]. The [[Dominion of Newfoundland]] was directly ruled as a royal colony from 1933 to 1949, run by a governor appointed by London who made the decisions regarding Newfoundland.

====Asia====
{{Further|India in World War II|Indian Army during World War II}}

[[British Raj|British India]] included the areas and peoples covered by later [[India]], [[Bangladesh]], [[Pakistan]] and (until 1937) [[Myanmar|Burma/Myanmar]], which later became a separate colony.

[[British Malaya]] covers the areas of [[Peninsular Malaysia]] and [[Singapore in the Straits Settlements|Singapore]], while [[British Borneo]] covers the area of [[Brunei]], including [[Sabah]] and [[Sarawak]] of Malaysia.

[[British Hong Kong]] consisted of [[Hong Kong Island]], the [[Kowloon Peninsula]], and the [[New Territories]].

Territories controlled by the [[Colonial Office]], namely the [[Crown colony|Crown Colonies]], were controlled politically by the UK and therefore also entered hostilities with Britain's declaration of war. At the outbreak of World War II, the [[British Indian Army]] numbered 205,000 men. Later during World War II, the [[Indian Army during World War II|British Indian Army]] became the largest all-volunteer force in history, rising to over 2.5&nbsp;million men in size.

Indian soldiers earned 30 [[Victoria Cross]]es during the Second World War. It suffered 87,000 military casualties (more than any Crown colony but fewer than the United Kingdom). The UK suffered 382,000 military casualties.

[[Sheikhdom of Kuwait|Kuwait]] was a protectorate of the United Kingdom formally established in 1899. The [[Trucial States]] were British protectorates in the Persian Gulf.

[[Mandatory Palestine|Palestine]] was a mandate dependency created in the peace agreements after [[World War I]] from the former territory of the [[Ottoman Empire]], [[Mandatory Iraq|Iraq]].

====Europe====
The [[Cyprus Regiment]] was formed by the British Government during the Second World War and made part of the British Army structure. It was mostly [[Greek Cypriots|Greek Cypriot]] volunteers and [[Turkish Cypriots|Turkish Cypriot]] inhabitants of Cyprus but also included other Commonwealth nationalities. On a brief visit to Cyprus in 1943, Winston Churchill praised the "soldiers of the Cyprus Regiment who have served honourably on many fields from Libya to Dunkirk". About 30,000 Cypriots served in the Cyprus Regiment. The regiment was involved in action from the very start and served at [[Dunkirk]], in the [[Battle of Greece|Greek Campaign]] (about 600 soldiers were captured in [[Kalamata]] in 1941), North Africa ([[Operation Compass]]), France, the Middle East and Italy. Many soldiers were taken prisoner especially at the beginning of the war and were interned in various PoW camps ([[Stalag]]) including Lamsdorf ([[Stalag VIII-B]]), Stalag IVC at Wistritz bei Teplitz and Stalag 4b near Most in the Czech Republic. The soldiers captured in Kalamata were transported by train to prisoner of war camps.

===France===
{{Main|France during World War II}}
{{Further|Liberation of France|Military history of France during World War II}}
[[File:Free French Foreign Legionnairs.jpg|thumb|[[Free French]] forces at the [[Battle of Bir Hakeim]], 1942]]

====War declared====
[[File:P-40F GCII-5 Casablanca 9Jan43.jpg|thumb|FAFL Free French ''GC II/5 "LaFayette"'' receiving ex-USAAF [[Curtiss P-40]] fighters at [[Casablanca]], French Morocco]]
[[File:Bundesarchiv Bild 101I-027-1451-10, Toulon, Panzer IV.jpg|thumb|[[Scuttling of the French fleet in Toulon|The French fleet scuttled itself]] rather than fall into the hands of the Axis after their invasion of Vichy France on 11 November 1942.]]

After Germany invaded Poland, France [[French declaration of war on Germany (1939)|declared war on Germany]] on 3 September 1939.<ref name="Speeches that Reshaped the World">Speeches that Reshaped the World.</ref> In January 1940, French Prime Minister [[Édouard Daladier]] made a major speech denouncing the actions of Germany:
{{blockquote|At the end of five months of war, one thing has become more and more clear. It is that Germany seeks to establish a domination of the world completely different from any known in world history.

The domination at which the Nazis aim is not limited to the displacement of the balance of power and the imposition of the supremacy of one nation. It seeks the systematic and total destruction of those conquered by Hitler and it does not treaty with the nations which it has subdued. He destroys them. He takes from them their whole political and economic existence and seeks even to deprive them of their history and culture. He wishes only to consider them as vital space and a vacant territory over which he has every right.

The human beings who constitute these nations are for him only cattle. He orders their massacre or migration. He compels them to make room for their conquerors. He does not even take the trouble to impose any war tribute on them. He just takes all their wealth and, to prevent any revolt, he scientifically seeks the physical and moral degradation of those whose independence he has taken away.<ref name="Speeches that Reshaped the World" /> }}

France experienced several major phases of action during World War II:
* The "[[Phoney War]]" of 1939–1940, also called {{lang|fr|drôle de guerre}} in France, {{lang|pl|dziwna wojna}} in Poland (both meaning "Strange War"), or the {{lang|de|Sitzkrieg}} ("Sitting War", a pun on {{lang|de|[[Blitzkrieg]]}}) in Germany.
* The [[Battle of France]] in May–June 1940, which resulted in the defeat of the Allies, the fall of the [[French Third Republic]], the [[Occupation of France|German occupation of northern and western France]], and the creation of the rump state [[Vichy France]], which received diplomatic recognition from the Axis and most neutral countries including the [[United States]].<ref name="mondediplo_May2003_WhentheUSwantedtotakeoverFrance">{{cite web |url=http://mondediplo.com/2003/05/05lacroix |title=When the US wanted to take over France‑Le Monde diplomatique‑English edition |date=May 2003 |publisher=[[Le Monde diplomatique]] |access-date=10 December 2010 }}</ref>
* The period of [[French Resistance|resistance against the occupation]] and Franco-French struggle for control of the colonies between the Vichy regime and the [[Free French]], who continued the fight on the Allies' side after the [[Appeal of 18 June]] by General [[Charles de Gaulle]], recognized by the United Kingdom as France's government-in-exile. It culminated in the [[Allied landings in North Africa]] on 11 November 1942, when Vichy ceased to exist as an independent entity after having been invaded [[Case Anton|by both the Axis]] and the Allies simultaneously, being thereafter only the nominal government in charge during the occupation of France. Vichy forces in French North Africa switched allegiance and [[CFNL|merged with]] the Free French to participate in the campaigns [[Tunisian Campaign|of Tunisia]] and [[Italian Campaign (World War II)|of Italy]] and the invasion [[Italian occupation of Corsica#Operation Vesuvius|of Corsica]] in 1943–44.
* The [[Liberation of France|liberation of mainland France]] beginning with [[D-Day]] on 6 June 1944 and [[operation Overlord]], and then with [[operation Dragoon]] on 15 August 1944, leading to the [[Liberation of Paris]] on 25 August 1944 by the Free French [[2e Division Blindée]] and the installation of the [[Provisional Government of the French Republic]] in the newly liberated capital.
* Participation of the re-established provisional French Republic's [[First Army (France)|First Army]] in the [[Allied advance from Paris to the Rhine]] and the [[Western Allied invasion of Germany]] until [[Victory in Europe Day|V-E Day]] on 8 May 1945.

====Colonies and dependencies====
{{main|French colonial empire}}

===== Africa =====

In Africa these included: [[French West Africa]], [[French Equatorial Africa]], the League of Nations mandates of [[French Cameroun]] and [[French Togoland]], [[French Madagascar]], [[French Somaliland]], and the protectorates of [[French Tunisia]] and [[French Morocco]].

[[French Algeria]] was then not a colony or dependency but a fully-fledged part of [[metropolitan France]].

===== Asia and Oceania =====
[[File:AWM 009747.jpg|thumb|The fall of [[Damascus]] to the Allies, late June 1941. A car carrying Free French commanders General [[Georges Catroux]] and General [[Paul Legentilhomme|Paul Louis Le Gentilhomme]] enters the city, escorted by French [[Circassians|Circassian]] cavalry (''Gardes Tcherkess'').]]

In Asia and Oceania France has several territories: [[French Polynesia]], [[Wallis and Futuna]], [[New Caledonia]], the [[New Hebrides]], [[French Indochina]], [[French India]], [[Leased Territory of Guangzhouwan|Guangzhouwan]], the mandates of [[Greater Lebanon]] and [[French Syria]]. The French government in 1936 attempted to grant independence to its mandate of [[Mandatory Syrian Republic|Syria]] in the [[Franco-Syrian Treaty of Independence (1936)|Franco-Syrian Treaty of Independence of 1936]] signed by France and Syria. However, opposition to the treaty grew in France and the treaty was not ratified. Syria had become an official republic in 1930 and was largely self-governing. In 1941, a British-led invasion supported by Free French forces expelled Vichy French forces in [[Operation Exporter]].

===== Americas =====

France had several colonies in America, namely [[Martinique]], [[Guadeloupe]], [[French Guiana]] and [[Saint Pierre and Miquelon]].

===Soviet Union===
{{Further|Soviet Union in World War II|label1=Military history of the Soviet Union during World War II}}
[[File:RIAN archive 613694 Red Army men are on offensive near Bryansk.jpg|thumb|Soviet soldiers and [[T-34]] tanks advancing near Bryansk in 1942]]
[[File:Stalingrad - ruined city.jpg|thumb|Soviet soldiers fighting in the ruins of [[Volgograd#Stalingrad|Stalingrad]] during the [[Battle of Stalingrad]]]]
[[File:RIAN archive 225 IL-2 attacking.jpg|thumb|Soviet [[Il-2]] ground attack aircraft attacking German ground forces during the [[Battle of Kursk]], 1943]]

====History====

In the lead-up to the war between the Soviet Union and Nazi Germany, relations between the two states underwent several stages. [[General Secretary of the Soviet Union|General Secretary]] [[Joseph Stalin]] and the government of the Soviet Union had supported so-called [[popular front]] movements of [[Anti-fascism|anti-fascists]] including communists and non-communists from 1935 to 1939.<ref name="Paul Bushkovitch 2012. P. 390">Paul Bushkovitch. ''A Concise History of Russia''. Cambridge; New York: Cambridge University Press, 2012. pp.&nbsp;390–391.</ref> The popular front strategy was terminated from 1939 to 1941, when the Soviet Union cooperated with Germany in 1939 in the occupation and partitioning of Poland. The Soviet leadership refused to endorse either the Allies or the Axis from 1939 to 1941, as it called the Allied-Axis conflict an "imperialist war".<ref name="Paul Bushkovitch 2012. P. 390" />

Stalin had studied Hitler, including reading ''[[Mein Kampf]]'', and from it knew of Hitler's motives for destroying the Soviet Union.<ref>Kees Boterbloem. ''A History of Russia and Its Empire: From Mikhail Romanov to Vladimir Putin''. p. 235.</ref> As early as in 1933, the Soviet leadership voiced its concerns with the alleged threat of a potential German invasion of the country should Germany attempt a conquest of [[Lithuania]], [[Latvia]], or [[Estonia]], and in December 1933 negotiations began for the issuing of a joint Polish-Soviet declaration guaranteeing the sovereignty of the three Baltic countries.<ref name="David L. Ransel 2005. P184">David L. Ransel, Bozena Shallcross. ''Polish Encounters, Russian Identity''. Indiana University Press, 2005. p. 184.</ref> However, Poland withdrew from the negotiations following German and Finnish objections.<ref name="David L. Ransel 2005. P184" /> The Soviet Union and Germany at this time competed with each other for influence in Poland.<ref>Jan Karski. ''The Great Powers and Poland: From Versailles to Yalta''. Rowman & Littlefield, 2014. p. 197.</ref>

On 20 August 1939, forces of the [[Union of Soviet Socialist Republics]] under General [[Georgy Zhukov]], together with the [[People's Republic of Mongolia]] eliminated the threat of conflict in the east with a victory over Imperial Japan at the [[Battle of Khalkhin Gol]] in eastern Mongolia.

On the same day, Soviet party leader [[Joseph Stalin]] received a telegram from German Chancellor [[Adolf Hitler]], suggesting that German Foreign Minister [[Joachim von Ribbentrop]] fly to Moscow for diplomatic talks. (After receiving a lukewarm response throughout the spring and summer, Stalin abandoned attempts for a better diplomatic relationship with France and the United Kingdom.)<ref>Overy 1997, pp. 41, 43–47.</ref>

On 23 August, Ribbentrop and Soviet Foreign Minister [[Vyacheslav Molotov]] signed [[Molotov–Ribbentrop Pact|the non-aggression pact]] including secret protocols dividing Eastern Europe into defined "spheres of influence" for the two regimes, and specifically concerning the partition of the Polish state in the event of its "territorial and political rearrangement".<ref>Davies 2006, pp. 148–151.</ref>

On 15 September 1939, Stalin concluded a durable ceasefire with Japan, to take effect the following day (it would be upgraded to [[Soviet–Japanese Neutrality Pact|a non-aggression pact]] in April 1941).<ref>Davies 2006, pp 16, 154.</ref> The day after that, 17 September, Soviet forces [[Soviet invasion of Poland|invaded Poland from the east]]. Although some fighting continued until 5 October, the two invading armies held at least one joint [[German–Soviet military parade in Brest-Litovsk|military parade on 25 September]], and reinforced their non-military partnership with the [[German–Soviet Treaty of Friendship, Cooperation and Demarcation]] on 28 September. German and Soviet cooperation against Poland in 1939 has been described as [[co-belligerence]].<ref>{{Cite journal|last=Hager|first=Robert P.|date=1 March 2017|title="The laughing third man in a fight": Stalin's use of the wedge strategy|url=https://online.ucpress.edu/cpcs/article-abstract/50/1/15/607/The-laughing-third-man-in-a-fight-Stalin-s-use-of?redirectedFrom=fulltext|journal=Communist and Post-Communist Studies|language=en|volume=50|issue=1|pages=15–27|doi=10.1016/j.postcomstud.2016.11.002|issn=0967-067X|quote=The Soviet Union participated as a cobelligerent with Germany after September 17, 1939, when Soviet forces invaded eastern Poland|via=}}</ref><ref>{{Cite journal|last=Blobaum|first=Robert|date=1990|title=The Destruction of East-Central Europe, 1939–41|url=https://heinonline.org/HOL/Page?handle=hein.journals/probscmu39&id=686&div=&collection=|journal=Problems of Communism|volume=39|pages=106|quote=As a co-belligerent of Nazi Germany, the Soviet Union secretly assisted the German invasion of central and western Poland before launching its own invasion of eastern Poland on September 17|via=}}</ref>

On 30 November, the Soviet Union [[Winter War|attacked Finland]], for which it was expelled from the [[League of Nations]]. In the following year of 1940, while the world's attention was focused upon the German invasion of France and Norway,<ref>{{cite book |last1=Khudoley |first1=Konstantin K. |title=The Baltic question during the Cold War |publisher=Psychology Press |others=Vahur Made, David J. Smith |year=2009 |isbn=978-0-415-37100-1 |editor1-last=Hiden |editor1-first=John |page=57 |chapter=The Baltic factor |author-link=Konstantin Khudoley}}</ref> the USSR militarily<ref>{{cite book |last1=Geoffrey |first1=Roberts |editor1-first=Gordon |editor1-last=Martel |title=The World War Two reader |year=2004 |publisher=Routledge |isbn=978-0-415-22402-4 |page=88 |chapter=Ideology, calculation, and improvisation. Sphere of influence and Soviet foreign policy 1939–1945 |chapter-url=https://books.google.com/books?id=E-w9nzoRI3wC&pg=PA88}}</ref> [[Occupation of the Baltic states|occupied and annexed Estonia, Latvia, and Lithuania]]<ref>{{cite journal |last1=Roberts |first1=Geoffrey |year=1995 |title=Soviet policy and the Baltic States, 1939–1940 a reappraisal |journal=Diplomacy & Statecraft |volume=6 |issue=3 |pages=672–700 |publisher=Francis & Taylor |doi=10.1080/09592299508405982}}</ref> as well as parts of [[Kingdom of Romania|Romania]].

German-Soviet treaties were brought to an end by the [[Operation Barbarossa|German surprise attack on the USSR]] on 22 June 1941. After the invasion of the Soviet Union in 1941, Stalin endorsed the Western Allies as part of a renewed popular front strategy against Germany and called for the international communist movement to make a coalition with all those who opposed the Nazis.<ref name="Paul Bushkovitch 2012. P. 390" /> The Soviet Union soon entered in alliance with the United Kingdom. Following the USSR, a number of other [[communist]], pro-Soviet or Soviet-controlled forces fought against the [[Axis powers of World War II|Axis]] powers during the Second World War. They were as follows: the [[Albanian National Liberation Front]], the [[Chinese Red Army]], the [[National Liberation Front (Greece)|Greek National Liberation Front]], the [[Hukbalahap]], the [[Malayan Communist Party]], the [[People's Republic of Mongolia]], the [[Ludowe Wojsko Polskie|Polish People's Army]], the [[Tuvan People's Republic]] (annexed by the Soviet Union in 1944),<ref name="alatau">Toomas Alatalu. Tuva. A State Reawakens. ''Soviet Studies'', Vol. 44, No. 5 (1992), pp. 881–895</ref> the [[Viet Minh]] and the [[Yugoslav Partisans]].

The Soviet Union intervened against Japan and its [[Manchukuo|client state]] in [[Manchuria]] in 1945, cooperating with the [[Nationalist Government]] of China and the [[Kuomintang|Nationalist Party]] led by [[Chiang Kai-shek]]; though also cooperating, preferring, and encouraging the [[Chinese Communist Party]] led by [[Mao Zedong]] to take effective control of Manchuria after expelling Japanese forces.<ref>The Soviet Union and Communist China, 1945–1950: The Road to Alliance. p. 78.</ref>

===United States===
{{Further|Military history of the United States during World War II}}
[[File:Navy fighters during the attack on the Japanese fleet off Midway, June 4th to 6th 1942. In the center is visible a... - NARA - 520591.tif|thumb|American [[Douglas SBD Dauntless]] dive-bomber aircraft attacking the [[Japanese cruiser Mikuma|Japanese cruiser ''Mikuma'']] during the [[Battle of Midway]] in June 1942]]
[[File:Marines rest in the field on Guadalcanal.jpg|thumb|U.S. Marines during the [[Guadalcanal Campaign]] in November 1942]]
[[File:The Sandman a B-24 Liberator, piloted by Robert Sternfels.jpg|thumb|American [[Consolidated B-24 Liberator]] bomber aircraft during the bombing of [[Oil refinery|oil refineries]] in [[Ploiești]], Romania on 1 August 1943 during [[Operation Tidal Wave]]]]
[[File:Into the Jaws of Death 23-0455M edit.jpg|thumb|U.S. soldiers departing landing craft during the [[Normandy landings]] on 6 June 1944 known as [[D-Day]]]]

====War justifications====

The United States had indirectly supported Britain's war effort against Germany up to 1941 and declared its opposition to territorial aggrandizement. Materiel support to Britain was provided while the U.S. was officially neutral via the [[Lend-Lease]] Act starting in 1941.

President [[Franklin D. Roosevelt]] and Prime Minister [[Winston Churchill]] in August 1941 promulgated the [[Atlantic Charter]] that pledged commitment to achieving "the final destruction of Nazi tyranny".<ref>{{cite book|first=Frank|last=Freidel|title=Franklin D. Roosevelt: A Rendezvous with Destiny|url=https://books.google.com/books?id=fRN2zUV5zNEC&pg=PT350|year=2009 |page=350|publisher=Little, Brown |isbn=978-0316092418}}</ref> Signing the Atlantic Charter, and thereby joining the "United Nations" was the way a state joined the Allies, and also became eligible for membership in the [[United Nations]] world body that formed in 1945.

The US strongly supported the Nationalist Government in China in its war with Japan, and provided military equipment, supplies, and volunteers to the Nationalist Government of China to assist in its war effort.<ref>{{cite book|author=Jonathan G. Utley|title=Going to War with Japan, 1937–1941|url=https://books.google.com/books?id=zCZj934XUK8C|year=2005|publisher=Fordham Univ Press|isbn=978-0823224722}}</ref> In December 1941 Japan opened the war with its [[attack on Pearl Harbor]], the US declared war on Japan, and Japan's allies Germany and Italy declared war on the US, bringing the US into World War II.

The US played a central role in liaising among the Allies and especially among the Big Four.<ref>{{Cite book|url=https://books.google.com/books?id=q2iSO2hS2PkC&q=%22central+role+in+liaison%22&pg=PA96|title=United States Army in World War II: The War Department|date=1951|page=96|publisher=Department of the Army|language=en}}</ref> At the [[Arcadia Conference]] in December 1941, shortly after the US entered the war, the US and Britain established a [[Combined Chiefs of Staff]], based in Washington, which deliberated the military decisions of both the US and Britain.

====History====

On 8 December 1941, following the attack on Pearl Harbor, the United States Congress declared war on Japan at the request of President [[Franklin D. Roosevelt]]. This was followed by Germany and Italy declaring war on the United States on 11 December, bringing the country into the European theatre.

The US led Allied forces in the Pacific theatre against Japanese forces from 1941 to 1945. From 1943 to 1945, the US also led and coordinated the Western Allies' war effort in Europe under the leadership of General [[Dwight D. Eisenhower]].

The surprise attack on Pearl Harbor followed by Japan's swift attacks on Allied locations throughout the Pacific, resulted in major US losses in the first several months in the war, including losing control of the [[Commonwealth of the Philippines|Philippines]], [[Guam]], [[Wake Island]] and several Aleutian islands including [[Attu Island|Attu]] and [[Kiska]] to Japanese forces. American naval forces attained some early successes against Japan. One was the bombing of Japanese industrial centres in the [[Doolittle Raid]]. Another was repelling a Japanese invasion of [[Port Moresby]] in [[New Guinea]] during the [[Battle of the Coral Sea]].<ref>Chris Henry. ''The Battle of the Coral Sea''. London: Compendium Publishing; Annapolis, Maryland: Naval Institute Press, 2003. p. 84.</ref>

A major turning point in the Pacific War was the [[Battle of Midway]] where American naval forces were outnumbered by Japanese forces that had been sent to Midway to draw out and destroy American aircraft carriers in the Pacific and seize control of Midway that would place Japanese forces in proximity to Hawaii.<ref>Keegan, John. ''The Second World War.'' New York: Penguin, 2005. (275)</ref> However American forces managed to sink four of Japan's six large aircraft carriers that had initiated the attack on Pearl Harbor along with other attacks on Allied forces. Afterwards, the US began an offensive against Japanese-captured positions. The [[Guadalcanal Campaign]] from 1942 to 1943 was a major contention point where Allied and Japanese forces struggled to gain control of [[Guadalcanal]].

====Colonies and dependencies====

=====In the Americas and the Pacific=====

The United States held multiple dependencies in the Americas, such as [[Territory of Alaska|Alaska]], the [[Panama Canal Zone]], [[Puerto Rico]], and the [[Virgin Islands of the United States|U.S. Virgin Islands]].

In the Pacific it held multiple island dependencies such as [[American Samoa]], [[Guam]], [[Territory of Hawaii|Hawaii]], [[Midway Islands]], [[Wake Island]] and others. These dependencies were directly involved in the Pacific campaign of the war.

=====In Asia=====
[[File:FortMcKinley.jpg|thumb|[[Philippine Scouts]] at [[Fort William McKinley]] firing a 37&nbsp;mm anti-tank gun in training]]

The [[Commonwealth of the Philippines]] was a sovereign protectorate referred to as an "associated state" of the United States. From late 1941 to 1944, the Philippines was [[Japanese occupation of the Philippines|occupied by Japanese forces]], who established the [[Second Philippine Republic]] as a client state that had nominal control over the country.

===China===
{{Main|Second Sino-Japanese War}}

In the 1920s the Soviet Union provided military assistance to the [[Kuomintang]], or the Nationalists, and helped reorganize their party along [[Leninist]] lines: a unification of party, state, and army. In exchange the Nationalists agreed to let members of the [[Chinese Communist Party]] join the Nationalists on an individual basis. However, following the nominal unification of China at the end of the [[Northern Expedition]] in 1928, [[Generalissimo]] [[Chiang Kai-shek]] purged leftists from his party and fought against the revolting Chinese Communist Party, former [[warlord]]s, and other militarist factions.

A fragmented China provided easy opportunities for Japan to gain territories piece by piece without engaging in [[total war]]. Following the 1931 [[Mukden Incident]], the puppet state of [[Manchukuo]] was established. Throughout the early to mid-1930s, Chiang's anti-communist and anti-militarist campaigns continued while he fought small, incessant conflicts against Japan, usually followed by unfavorable settlements and concessions after military defeats.

In 1936 Chiang was forced to cease his [[Nanjing decade|anti-communist military campaigns]] after [[Xi'an incident|his kidnap and release]] by [[Zhang Xueliang]], and reluctantly formed [[Second United Front (China)|a nominal alliance]] with the Communists, while the Communists agreed to fight under the nominal command of the Nationalists against the Japanese. Following the [[Marco Polo Bridge Incident]] of 7 July 1937, China and Japan became embroiled in a full-scale war. The Soviet Union, wishing to keep China in the fight against Japan, supplied China with military assistance until 1941, when it [[Soviet-Japanese Treaty (1941)|signed a non-aggression pact with Japan]].

In December 1941 after the attack on Pearl Harbor, China formally declared war on Japan, as well as Germany and Italy. As part of the war's [[Pacific War|Pacific theater]], China became the only member of the Allies to commit more troops than one of the Big Three,<ref>{{cite book |last = Hastings |first = Max |title = Retribution |year = 2008 |publisher = Knopf Doubleday Publishing Group |isbn = 978-0307263513 |url = https://archive.org/details/retributionbattl00hast |page = 205 }}</ref> exceeding even the number of Soviet troops on the [[Eastern Front (World War II)|Eastern Front]].<ref>{{cite book |last1= Glantz |first1= David M. |last2= House |first2= Jonathan M. |date= 2015 |title= When Titans Clashed: How the Red Army Stopped Hitler |url= https://books.google.com/books?id=WS2ArgEACAAJ&pg=PA301 |edition= Second |series= Modern War Studies |publisher= University Press of Kansas |isbn= 978-0-7006-2121-7 |pages= 301–303}}</ref>

Continuous clashes between the Communists and Nationalists behind enemy lines cumulated in [[New Fourth Army Incident|a major military conflict]] between these two former allies that effectively ended their cooperation against the Japanese, and China had been divided between the internationally recognized [[Nationalist Government|Nationalist China]] under the leadership of Generalissimo Chiang Kai-shek and [[Communist-controlled China (1927–49)|Communist China]] under the leadership of [[Mao Zedong]] until the Japanese surrendered in 1945.

====Factions====

=====Nationalists=====
{{Main|Nationalist Government}}
[[File:Kmtarmy.JPG|thumb|upright|Soldiers of the [[National Revolutionary Army]] associated with Nationalist China, during the Second Sino-Japanese War]]

Prior to the alliance of Germany and Italy to Japan, the Nationalist Government held close relations with both Germany and Italy. In the early 1930s, [[Sino-German cooperation]] existed between the Nationalist Government and Germany in military and industrial matters. Nazi Germany provided the largest proportion of Chinese arms imports and technical expertise. Relations between the Nationalist Government and Italy during the 1930s varied, however even after the Nationalist Government followed League of Nations sanctions against Italy for [[Second Italo-Ethiopian War|its invasion]] of [[Ethiopian Empire|Ethiopia]], the international sanctions proved unsuccessful, and relations between the Fascist government in Italy and the Nationalist Government in China returned to normal shortly afterwards.<ref name="G. Bruce Strang 2003. Pp. 58-59">G. Bruce Strang. On the fiery march: Mussolini prepares for war. Westport, Connecticut, US: Greenwood Publishing Group, Inc., 2003. pp.&nbsp;58–59.</ref>

Up until 1936, Mussolini had provided the Nationalists with Italian military air and naval missions to help the Nationalists fight against Japanese incursions and communist insurgents.<ref name="G. Bruce Strang 2003. Pp. 58-59" /> Italy also held strong commercial interests and a strong commercial position in China supported by the [[Italian concession in Tianjin]].<ref name="G. Bruce Strang 2003. Pp. 58-59" /> However, after 1936 the relationship between the Nationalist Government and Italy changed due to a Japanese diplomatic proposal to recognize the [[Italian Empire]] that included occupied Ethiopia within it in exchange for Italian recognition of [[Manchukuo]], Italian Foreign Minister [[Galeazzo Ciano]] accepted this offer by Japan, and on 23 October 1936 Japan recognized the Italian Empire and Italy recognized Manchukuo, as well as discussing increasing commercial links between Italy and Japan.<ref>G. Bruce Strang. On the fiery march: Mussolini prepares for war. Westport, Connecticut, US: Greenwood Publishing Group, Inc., 2003. pp.&nbsp;59–60.</ref>

The Nationalist Government held close relations with the [[United States]]. The United States opposed Japan's invasion of China in 1937 that it considered an illegal violation of China's [[sovereignty]], and offered the Nationalist Government diplomatic, economic, and military assistance during its war against Japan. In particular, the United States sought to bring the Japanese war effort to a complete halt by imposing a full embargo on all trade between the United States to Japan, Japan was dependent on the United States for 80 per cent of its [[petroleum]], resulting in an economic and military crisis for Japan that could not continue its war effort with China without access to petroleum.<ref>Euan Graham. ''Japan's sea lane security, 1940–2004: a matter of life and death?'' Oxon, England; New York: Routledge, 2006. p. 77.</ref> In November 1940, American military aviator [[Claire Lee Chennault]] upon observing the dire situation in the air war between China and Japan, set out to organize a volunteer squadron of American fighter pilots to fight alongside the Chinese against Japan, known as the [[Flying Tigers]].<ref name="Col. C.L Pp. 16">Guo wu yuan. Xin wen ban gong shi. Col. C.L. Chennault and Flying Tigers. English translation. State Council Information Office of the People's Republic of China. pp. 16.</ref> US President [[Franklin D. Roosevelt]] accepted dispatching them to China in early 1941.<ref name="Col. C.L Pp. 16" /> However, they only became operational shortly after the attack on Pearl Harbor.

The [[Soviet Union]] recognised the [[Republic of China (1912–1949)|Republic of China]] but urged reconciliation with the Chinese Communist Party and inclusion of Communists in the government.<ref name="Frederic J. Fleron 2009. Pp. 236">Frederic J. Fleron, Erik P. Hoffmann, Robbin Frederick Laird. ''Soviet Foreign Policy: Classic and Contemporary Issues.'' Third paperback edition. New Brunswick, New Jersey, US: Transaction Publishers, 2009. Pp. 236.</ref> The Soviet Union also urged military and cooperation between Nationalist China and Communist China during the war.<ref name="Frederic J. Fleron 2009. Pp. 236" />

Even though China had been fighting the longest among all the Allied powers, it only officially joined the Allies after the attack on Pearl Harbor, on 7 December 1941. China fought the Japanese Empire before joining the Allies in the [[Pacific War]]. Generalissimo Chiang Kai-shek thought Allied victory was assured with the entrance of the United States into the war, and he declared war on Germany and the other Axis states. However, Allied aid remained low because the [[Burma Road]] was closed and the Allies suffered a series of military defeats against Japan early on in the campaign. General [[Sun Li-jen]] led the R.O.C. forces to the relief of 7,000 British forces trapped by the Japanese in the [[Battle of Yenangyaung]]. He then reconquered North Burma and re-established the land route to China by the [[Ledo Road]]. But the bulk of military aid did not arrive until the spring of 1945. More than 1.5&nbsp;million Japanese troops were trapped in the China Theatre, troops that otherwise could have been deployed elsewhere if China had collapsed and made a separate peace.

=====Communists=====
{{Main|Communist-controlled China (1927–1949)}}
[[File:Ba lu bing gong chang.jpg|thumb|Soldiers of the [[People's Liberation Army|First Workers' and Peasants' Army]] associated with Communist China, during the Sino-Japanese War]]
[[File:Hundred Regiments Offensive 1940.jpg|thumb|Victorious Chinese Communist soldiers holding the [[flag of the Republic of China]] during the [[Hundred Regiments Offensive]]]]

Communist China had been tacitly supported by the [[Soviet Union]] since the 1920s: though the Soviet Union diplomatically recognised the Republic of China, [[Joseph Stalin]] supported cooperation between the Nationalists and the Communists—including pressuring the Nationalist Government to grant the Communists state and military positions in the government.<ref name="Frederic J. Fleron 2009. Pp. 236" /> This was continued into the 1930s that fell in line with the Soviet Union's subversion policy of [[popular front]]s to increase communists' influence in governments.<ref name="Frederic J. Fleron 2009. Pp. 236" />

The Soviet Union urged military and cooperation between Communist China and Nationalist China during China's war against Japan.<ref name="Frederic J. Fleron 2009. Pp. 236" /> Initially [[Mao Zedong]] accepted the demands of the Soviet Union and in 1938 had recognized Chiang Kai-shek as the "leader" of the "Chinese people".<ref name="Dieter Heinzig 2004. Pp. 9">Dieter Heinzig. ''The Soviet Union and communist China, 1945–1950: the arduous road to the alliance''. M. E. Sharpe, 2004. p. 9.</ref> In turn, the Soviet Union accepted Mao's tactic of "continuous guerilla warfare" in the countryside that involved a goal of extending the Communist bases, even if it would result in increased tensions with the Nationalists.<ref name="Dieter Heinzig 2004. Pp. 9" />

After the breakdown of their cooperation with the Nationalists in 1941, the Communists prospered and grew as the war against Japan dragged on, building up their sphere of influence wherever opportunities were presented, mainly through rural mass organizations, administrative, land and tax reform measures favoring poor peasants; while the Nationalists attempted to neutralize the spread of Communist influence by military blockade and fighting the Japanese at the same time.<ref name="CRISIS-TIME-MAGAZINE">{{cite magazine|date=13 November 1944|title=Crisis|magazine=[[Time (magazine)|Time]]|url=http://www.time.com/time/magazine/article/0,9171,801570-4,00.html|archive-url=https://web.archive.org/web/20071120121411/http://www.time.com/time/magazine/article/0,9171,801570-4,00.html|url-status=dead|archive-date=20 November 2007}}</ref>

The Communist Party's position in China was boosted further upon the [[Soviet invasion of Manchuria]] in August 1945 against the Japanese puppet state of [[Manchukuo]] and the Japanese [[Kwantung Army]] in China and [[Manchuria]]. Upon the intervention of the Soviet Union against Japan in World War II in 1945, Mao Zedong in April and May 1945 had planned to mobilize 150,000 to 250,000 soldiers from across China to work with forces of the Soviet Union in capturing Manchuria.<ref>Dieter Heinzig. ''The Soviet Union and communist China, 1945–1950: the arduous road to the alliance''. M. E. Sharpe, 2004. p. 79.</ref>

==Other Allied states==

===Albania===
{{Further|World War II in Albania}}
Albania was retroactively recognized as an "Associated Power" at the 1946 Paris conference<ref>United States Department of State, Foreign relations of the United States, 1946. Paris Peace Conference : documents (1946), p. 802, Article 26.a 'Memoranda submitted by Albanian Government on the Draft Peace Treaty with Italy' "proposed amendment...For the purposes of this Treaty, Albania shall be considered as an Associated Power.", web http://images.library.wisc.edu/FRUS/EFacs/1946v04/reference/frus.frus1946v04.i0011.pdf</ref> and officially signed the treaty ending WWII between the "Allied and Associated Powers" and Italy in Paris, on 10 February 1947.<ref>[http://2009-2017.state.gov/documents/organization/218912.pdf ''Treaties in Force, A List of Treaties and Other International Agreements of the United States in Force on January 1, 2013''], p. 453. From state.gov</ref><ref name="Encyclopedia of World War II, Volume 1">{{cite book|last1=Axelrod|first1=John|url=https://books.google.com/books?id=LbWFgjW6KX8C&q=WW2+allied+and+associated+powers+albania&pg=PA824|title=Encyclopedia of World War II|date= 2015|publisher=H W Fowler|isbn=978-1-84511-308-7|volume=1|page=824|quote=The first peace treaty concluded between the Allies and a former Axis nation was with Italy. It was signed in Paris on 10 February, by representatives from Albania, Australia ....}}</ref>

===Australia===
{{Further|Military history of Australia during World War II}}

Australia was a sovereign Dominion under the [[Monarchy of Australia|Australian monarchy]], as per the [[Statute of Westminster 1931]]. At the start of the war Australia followed Britain's foreign policies and accordingly declared war against Germany on 3 September 1939. Australian foreign policy became more independent after the [[Australian Labor Party]] formed government in October 1941, and Australia separately declared war against Finland, Hungary and Romania on 8 December 1941 and against Japan the next day.<ref>{{cite web|last1=McKeown|first1=Deirdre|last2=Jordan|first2=Roy|title=Parliamentary involvement in declaring war and deploying forces overseas|url=https://www.aph.gov.au/binaries/library/pubs/bn/pol/parliamentaryinvolvement.pdf|website=Parliamentary Library|publisher=Parliament of Australia|access-date=9 December 2015|pages=4, 8–11|date=2010}}</ref>

===Belgium===
{{Main|Belgium in World War II}}
[[File:Belgian res.jpg|thumb|Members of the Belgian Resistance with a Canadian soldier in [[Bruges]], September 1944 during the [[Battle of the Scheldt]]]]

Before the war, Belgium had pursued a policy of [[Neutrality (international relations)|neutrality]] and only became an Allied member after [[Battle of Belgium|being invaded]] by Germany on 10 May 1940. During the ensuing fighting, Belgian forces fought alongside French and British forces against the invaders. While the British and French were struggling against [[Blitzkrieg|the fast German advance]] elsewhere on the front, the Belgian forces were pushed into a pocket to the north. On 28 May, the [[Leopold III of Belgium|King Leopold III]] surrendered himself and his military to the Germans, having decided the Allied cause was lost.

The legal Belgian government was reformed as [[Belgian Government in Exile|a government in exile in London]]. Belgian troops and pilots continued to fight on the Allied side as the [[Free Belgian Forces]]. Belgium itself was occupied, but a sizeable [[Belgian Resistance|Resistance]] was formed and was loosely coordinated by the government in exile and other Allied powers.

British and Canadian troops arrived in Belgium in September 1944 and the capital, [[Brussels]], was liberated on 6 September. Because of the [[Ardennes Offensive]], the country was only fully liberated in early 1945.

====Colonies and dependencies====
{{main|Belgian colonial empire}}

Belgium held the colony of the [[Belgian Congo]] and the League of Nations mandate of [[Ruanda-Urundi]]. The Belgian Congo was not occupied and remained loyal to the Allies as an important economic asset while its deposits of uranium were useful to the Allied efforts to develop the atomic bomb. Troops from the Belgian Congo participated in the [[East African Campaign (World War II)|East African Campaign]] against the Italians. The colonial ''[[Force Publique]]'' also served in other theatres including Madagascar, the Middle-East, India and Burma within British units.

===Brazil===
{{Main|Brazilian Expeditionary Force}}Initially, [[Vargas Era|Brazil]] maintained a position of neutrality, trading with both the Allies and the [[Axis powers|Axis]], while Brazilian president [[Getúlio Vargas]]'s quasi-[[Fascist]] policies indicated a leaning toward the Axis powers.{{citation needed|date=April 2023}} However, as the war progressed, trade with the Axis countries became almost impossible and the United States initiated forceful diplomatic and economic efforts to bring Brazil onto the Allied side.{{citation needed|date=November 2021}}

At the beginning of 1942, Brazil permitted the United States to set up air bases on its territory, especially in [[Natal, Rio Grande do Norte|Natal]], strategically located at the easternmost corner of the [[South American]] continent, and on 28 January the country severed diplomatic relations with Germany, Japan and Italy. After that, 36 Brazilian merchant ships were sunk by the German and Italian navies, which led the Brazilian government to declare war against Germany and Italy on 22 August 1942.

Brazil then sent a 25,700 strong [[Expeditionary warfare|Expeditionary Force]] to Europe that fought mainly on the [[Italian Campaign (World War II)#Allied advance into Northern Italy|Italian front]], from September 1944 to May 1945. Also, the [[Brazilian Navy]] and [[Brazilian Air Force|Air Force]] acted in the [[Atlantic Ocean]] from the middle of 1942 until the end of the war. Brazil was the only South American country to send troops to fight in the European theatre in the Second World War.

===Canada===
{{Main|Declaration of war by Canada#Germany|Military history of Canada during World War II}}

Canada was a sovereign Dominion under the [[Monarchy of Canada|Canadian monarchy]], as per the Statute of Westminster 1931. In a symbolic statement of autonomous foreign policy Prime Minister [[William Lyon Mackenzie King]] delayed parliament's vote on a declaration of war for seven days after Britain had declared war. Canada was the last member of the Commonwealth to declare war on Germany on 10 September 1939.<ref>{{cite book|author=Phillip Alfred Buckner|title=Canada and the British Empire|url=https://books.google.com/books?id=KmXnLGX7FvEC&pg=PA105|year=2008|publisher=Oxford U.P.|pages=105–106|isbn=978-0199271641}}</ref>

===Cuba===
{{Main|Cuba during World War II}}

Because of [[Republic of Cuba (1902–1959)|Cuba]]'s geographical position at the entrance of the [[Gulf of Mexico]], [[Havana]]'s role as the principal trading port in the [[West Indies]], and the country's natural resources, Cuba was an important participant in the [[American Theater (1939–1945)|American Theater]] of World War II, and subsequently one of the greatest beneficiaries of the [[United States]]' [[Lend-Lease]] program. Cuba declared war on the [[Axis powers]] in December 1941,<ref name="narod.ru">{{cite web | title=Second World War and the Cuban Air Force| url=http://www.urrib2000.narod.ru/Mil1-4-e.html| access-date=6 February 2013}}</ref> making it one of the first [[Latin America]]n countries to enter the conflict, and by the war's end in 1945 its military had developed a reputation as being the most efficient and cooperative of all the Caribbean states.<ref name="Polmar, pg. 230">{{cite book | last=Polmar| first=Norman|author2=Thomas B. Allen| title=World War II: The Encyclopedia of the War Years 1941–1945| year=1991| publisher=Random House| isbn=978-0394585307| url=https://archive.org/details/worldwariiameric00polm| url-access=registration}}</ref> On 15 May 1943, the Cuban patrol boat CS-13 sank the German submarine ''[[U-176]]''.<ref name="Morison, pg. 190">{{cite book | last=Morison| first=Samuel Eliot| title=History of United States Naval Operations in World War II: The Atlantic | publisher=University of Illinois Press| year=2002| isbn=0-252-07061-5}}</ref><ref name="cubanow.net">{{cite web| title=Cubans Sunk a German Submarine in WWII| work=Cubanow| url=http://www.cubanow.net/articles/cubans-sunk-german-submarine-wwii| access-date=6 February 2013| url-status=dead| archive-url=https://web.archive.org/web/20141220133827/http://www.cubanow.net/articles/cubans-sunk-german-submarine-wwii| archive-date=20 December 2014}}</ref>

===Czechoslovakia===
{{Further|German occupation of Czechoslovakia|Czechoslovak government-in-exile}}

In 1938, with the [[Munich Agreement]], Czechoslovakia, the United Kingdom, and France sought to resolve German irredentist claims to the [[Sudetenland]] region. As a result, the incorporation of the Sudetenland into Germany began on 1 October 1938. Additionally, a small northeastern part of the border region known as [[Trans-Olza]] was occupied by and annexed to [[Polish Second Republic|Poland]]. Further, by the [[First Vienna Award]], [[Kingdom of Hungary (1920–1946)|Hungary]] received southern territories of Slovakia and [[Carpathian Ruthenia]].

A [[Slovak State]] was proclaimed on 14 March 1939, and the next day Hungary occupied and annexed the remainder of Carpathian Ruthenia, and the German ''[[Wehrmacht]]'' moved into the remainder of the Czech Lands. On 16 March 1939 the [[Protectorate of Bohemia and Moravia]] was proclaimed after negotiations with [[Emil Hácha]], who remained technically head of state with the title of State President. After a few months, former Czechoslovak President Beneš organized a committee in exile and sought diplomatic recognition as the legitimate government of the [[First Czechoslovak Republic]]. The committee's success in obtaining intelligence and coordinating actions by the [[Resistance in the Protectorate of Bohemia and Moravia|Czechoslovak resistance]] led first Britain and then the other Allies to recognize it in 1941. In December 1941 the [[Czechoslovak government-in-exile]] declared war on the Axis powers. Czechoslovakian military units took part in the war.

===Dominican Republic===

The Dominican Republic was one of the very few countries willing to accept mass Jewish immigration during [[World War II]]. At the [[Évian Conference]], it offered to accept up to 100,000 Jewish refugees.<ref>{{cite web|url=http://www.ushmm.org/wlc/article.php?lang=en&ModuleId=10005468|title=German Jewish Refugees, 1933–1939|publisher=United States Holocaust Memorial Museum|access-date=1 June 2017}}</ref> The DORSA (Dominican Republic Settlement Association) was formed with the assistance of the JDC, and helped settle Jews in [[Sosúa]], on the northern coast. About 700 European Jews of [[Ashkenazi]] Jewish descent reached the settlement where each family received {{Convert|33|ha}} of land, 10 cows (plus 2 additional cows per children), a mule and a horse, and a [[United States dollar|US$]]10,000 loan (equivalent to about ${{Inflation|US|10000|1941|r=-3|fmt=c}} in {{inflation/year|US}}{{inflation/fn|US}}) at 1% interest.<ref name="MuKienAdrianaSang">{{cite web|url=http://www.elcaribe.com.do/2012/11/16/judios-caribe.-comunidad-judia-sosua-2|title=Judíos en el Caribe. La comunidad judía en Sosúa (2)|last=Sang|first=Mu-Kien Adriana|author-link=Mu-Kien Adriana Sang|date=16 November 2012|publisher=El Caribe|language=es|access-date=29 May 2014|url-status=dead|archive-url=https://web.archive.org/web/20140529071312/http://www.elcaribe.com.do/2012/11/16/judios-caribe.-comunidad-judia-sosua-2|archive-date=29 May 2014}}</ref><ref>{{cite web|url=https://www.jewishvirtuallibrary.org/jsource/Holocaust/sosua.html|title=Dominican Republic as Haven for Jewish Refugees|website=www.jewishvirtuallibrary.org|access-date=1 June 2017}}</ref>

The Dominican Republic officially declared war on the Axis powers on 11 December 1941, after the [[attack on Pearl Harbor]]. However, the Caribbean state had already been engaged in war actions since before the formal declaration of war. Dominican sailboats and schooners had been attacked on previous occasions by German submarines as, highlighting the case of the 1,993-ton merchant ship, ''San Rafael'', which was making a trip from [[Tampa, Florida]] to [[Kingston, Jamaica]], when 80 miles away from its final destination, it was torpedoed by the [[German submarine U-125 (1940)|German submarine U-125]], causing the commander to order the ship abandoned. Although the crew of ''San Rafael'' managed to escape the event, it would be remembered by the Dominican press as a sign of the "infamy of the German submarines and the danger they represented in the Caribbean".{{attribution needed|date=June 2023}}<ref>{{Cite news|url=https://www.listindiario.com/la-republica/2012/7/24/240871/El-heroe-de-La-Batalla-del-Caribe|title=El heroe de La Batalla del Caribe|last=Lajara Solá|first=Homero Luis|date=24 July 2012|work=Listín Dairio|access-date=10 May 2018|archive-date=22 March 2018|archive-url=https://web.archive.org/web/20180322020637/https://www.listindiario.com/la-republica/2012/7/24/240871/El-heroe-de-La-Batalla-del-Caribe|url-status=dead}}</ref>

Recently, due to a research work carried out by the Embassy of the United States of America in Santo Domingo and the [[Institute of Dominican Studies of the City of New York]] (CUNY), documents of the [[United States Department of Defense|Department of Defense]] were discovered in which it was confirmed that around 340 men and women of Dominican origin were part of the US Armed Forces during the World War II. Many of them received medals and other recognitions for their outstanding actions in combat.<ref>{{Cite web|url=https://do.usembassy.gov/es/embassy-of-the-united-states-and-the-memorial-museum-of-resistance-open-exposition-in-honor-of-dominican-veterans-of-the-second-world-war-es/|title=Embajada de los Estados Unidos y el Museo Memorial de la Resistencia Abren Exposición en honor a Veteranos Dominicanos de la Segunda Guerra Mundial|date=9 August 2016|website=Embajada de los Estados Unidos en la República Dominicana}}</ref>

===Ethiopia===
The Ethiopian Empire was [[Second Italo-Ethiopian War|invaded]] by [[Fascist Italy (1922–1943)|Italy]] on 3 October 1935. On 2 May 1936, Emperor [[Haile Selassie I]] fled into exile, just before the Italian occupation on 7 May. After the outbreak of World War II, the Ethiopian government-in-exile cooperated with the British during the [[East African campaign (World War II)|British Invasion of Italian East Africa]] beginning in June 1940. Haile Selassie returned to his rule on 18 January 1941. Ethiopia declared war on Germany, Italy and Japan in December 1942.

===Greece===
{{Further|Military history of Greece during World War II|Axis occupation of Greece|Greek Resistance}}Greece was [[Greco-Italian War|invaded by Italy]] on 28 October 1940 and subsequently joined the Allies. The Greek Army managed to stop the Italian offensive from Italy's protectorate of Albania, and Greek forces pushed Italian forces back into Albania. However, after the [[German invasion of Greece]] in April 1941, German forces managed to occupy mainland Greece and, a month later, [[Battle of Crete|the island of Crete]]. The Greek government [[Greek government in exile|went into exile]], while the country was placed under [[Hellenic State (1941–44)|a puppet government]] and divided into occupation zones run by Italy, Germany and Bulgaria.

From 1941, a strong resistance movement appeared, chiefly in the mountainous interior, where it established a "Free Greece" by mid-1943. Following the Italian capitulation in September 1943, the Italian zone was taken over by the Germans. Axis forces left mainland Greece in October 1944, although some Aegean islands, notably Crete, remained under German occupation until the end of the war.

===Luxembourg===
{{Main|Luxembourg in World War II}}
{{See also|Luxembourgish government in exile|Luxembourg Resistance|Battle of the Bulge|Luxembourg American Cemetery and Memorial}}Before the war, Luxembourg had pursued a policy of [[Neutrality (international relations)|neutrality]] and only became an Allied member after [[Invasion of Luxembourg|being invaded]] by Germany on 10 May 1940. The government in exile fled, winding up in England. It made Luxembourgish language broadcasts to the occupied country on [[British Broadcasting Corporation|BBC radio]].<ref name=GduGD112>{{cite book|last=Various|title=Les Gouvernements du Grand-Duché de Luxembourg Depuis 1848|year=2011|publisher=Government of Luxembourg|location=Luxembourg|isbn=978-2-87999-212-9|page=112|url=http://www.gouvernement.lu/publications/gouvernement/gouvernements_depuis_1848/Les_gouvernements_depuis_1848.pdf|url-status=dead|archive-url=https://web.archive.org/web/20111016173644/http://www.gouvernement.lu/publications/gouvernement/gouvernements_depuis_1848/Les_gouvernements_depuis_1848.pdf|archive-date=16 October 2011}}</ref> In 1944, the government in exile signed [[London Customs Convention|a treaty]] with the Belgian and Dutch governments, creating the [[Benelux]] Economic Union and also signed into the [[Bretton Woods system]].

===Mexico===
{{Main|Mexico during World War II}}

[[Mexico]] declared war on Germany in 1942 after German submarines attacked the Mexican oil tankers ''[[SS Potrero del Llano|Potrero del Llano]]'' and ''[[Faja de Oro]]'' that were transporting crude oil to the [[United States]]. These attacks prompted [[President of Mexico|President]] [[Manuel Ávila Camacho]] to declare war on the Axis powers.

Mexico formed [[Escuadrón 201]] fighter squadron as part of the [[Fuerza Aérea Expedicionaria Mexicana]] (FAEM—"Mexican Expeditionary Air Force"). The squadron was attached to the [[58th Operations Group|58th Fighter Group]] of the [[United States Army Air Forces]] and carried out tactical air support missions during the liberation of the main Philippine island of [[Luzon]] in the summer of 1945.<ref>{{cite web |last = Klemen |first = L|title = 201st Mexican Fighter Squadron |url=https://warfare.gq/dutcheastindies/201squadron.html |work = The Netherlands East Indies 1941–1942}} 201st Mexican Fighter Squadron</ref>

Some 300,000 Mexican citizens went to the United States to work on farms and factories. Some 15,000 U.S. nationals of Mexican origin and Mexican residents in the US enrolled in the US Armed Forces and fought in various fronts around the world.<ref>Plascencia de la Parra, E. La infantería Invisible:Mexicanos en la Segunda Guerra Mundial.México. Ed. UNAM. Retrieved 27 April 2012 [http://www.lasegundaguerra.com/viewtopic.php?t=422&f=29]</ref>

===Netherlands===
{{Main|Netherlands in World War II}}

The Netherlands became an Allied member after being invaded on 10 May 1940 by Germany. During the [[Battle of the Netherlands|ensuing campaign]], the Netherlands were defeated and occupied by Germany. The Netherlands was liberated by Canadian, British, American and other allied forces during the campaigns of 1944 and 1945. The [[Royal Netherlands Motorized Infantry Brigade|Princess Irene Brigade]], formed from escapees from the German invasion, took part in several actions in 1944 in Arromanches and in 1945 in the Netherlands. Navy vessels saw action in the British Channel, the North Sea and the Mediterranean, generally as part of Royal Navy units. Dutch airmen flying British aircraft participated in the air war over Germany.

====Colonies and dependencies====
{{main|Dutch Empire}}

The [[Dutch East Indies]] (modern-day [[Indonesia]]) was the principal Dutch colony in Asia, and was seized by Japan in 1942. During the [[Dutch East Indies Campaign]], the Netherlands played a significant role in the Allied effort to halt the Japanese advance as part of the [[American-British-Dutch-Australian Command|American-British-Dutch-Australian (ABDA) Command]]. The ABDA fleet finally encountered the Japanese surface fleet at the [[Battle of Java Sea]], at which Doorman gave the order to engage. During the ensuing battle the ABDA fleet suffered heavy losses, and was mostly destroyed after several naval battles around [[Java]]; the ABDA Command was later dissolved. The Japanese [[Japanese occupation of the Dutch East Indies|finally occupied]] the Dutch East Indies in February–March 1942. Dutch troops, aircraft and escaped ships continued to fight on the Allied side and also mounted a [[Battle of Timor|guerrilla campaign in Timor]].

===New Zealand===
{{Further|Military history of New Zealand during World War II}}

New Zealand was a sovereign Dominion under the [[Monarchy of New Zealand|New Zealand monarchy]], as per the Statute of Westminster 1931. It quickly entered World War II, officially declaring war on Germany on 3 September 1939, just hours after Britain.<ref>{{cite news|url=http://www.nzhistory.net.nz/war/second-world-war/fighting-for-britain|title=Fighting for Britain – NZ and the Second World War|publisher=[[Ministry for Culture and Heritage (New Zealand)|Ministry for Culture and Heritage]]|date=2 September 2008}}</ref> Unlike Australia, which had felt obligated to declare war, as it also had not ratified the Statute of Westminster, New Zealand did so as a sign of allegiance to Britain, and in recognition of Britain's abandonment of its [[Appeasement of Hitler|former appeasement]] policy, which New Zealand had long opposed. This led to then Prime Minister [[Michael Joseph Savage]] declaring two days later:

{{blockquote|With gratitude for the past and confidence in the future we range ourselves without fear beside Britain. Where she goes, we go; where she stands, we stand. We are only a small and young nation, but we march with a union of hearts and souls to a common destiny.<ref>{{cite web|url=http://www.nzhistory.net.nz/pm-declares-new-zealands-support-for-britain-in-famous-radio-broadcast|archive-url=https://web.archive.org/web/20141126052232/http://www.nzhistory.net.nz/pm-declares-new-zealands-support-for-britain-in-famous-radio-broadcast|url-status=dead|archive-date=26 November 2014|title=PM declares NZ's support for Britain |work=New Zealand History Online|date=26 November 2014}}</ref>}}

===Norway===
{{Further|German occupation of Norway}}

[[File:Norwegian soldiers on the Narvik front.jpg|thumb|Norwegian soldiers on the [[Battles of Narvik#Land battle|Narvik front]], May 1940]]

Because of its strategic location for control of the sea lanes in the [[North Sea]] and the [[Atlantic]], both the Allies and Germany worried about the other side gaining control of the neutral country. Germany ultimately struck first with [[Operation Weserübung]] on 9 April 1940, resulting in the two-month-long [[Norwegian Campaign]], which ended in a German victory and their war-long [[occupation of Norway]].

Units of the Norwegian Armed Forces evacuated from Norway or raised abroad continued participating in the war [[Norwegian Armed Forces in exile|from exile]].

The Norwegian merchant fleet, then the fourth largest in the world, was organized into [[Nortraship]] to support the Allied cause. Nortraship was the world's largest shipping company, and at its height operated more than 1000 ships.

Norway was neutral when Germany invaded, and it is not clear when Norway became an Allied country. Great Britain, France and [[Polish Armed Forces in the West|Polish forces in exile]] supported Norwegian forces against the invaders but without a specific agreement. Norway's cabinet signed a military agreement with Britain on 28 May 1941. This agreement allowed all Norwegian forces in exile to operate under UK command. Norwegian troops in exile should primarily be prepared for the liberation of Norway, but could also be used to defend Britain. At the end of the war German forces in Norway surrendered to British officers on 8 May and [[Operation Doomsday|allied troops occupied Norway]] until 7 June.<ref name="Skodvin, Magne 1984">Skodvin, Magne (red.) (1984): ''Norge i krig.'' Bind 7. Oslo: Aschehoug.</ref>

===Poland===
{{Further|Polish contribution to World War II|Polish resistance movement in World War II|Polish Armed Forces in the West|Polish Armed Forces in the East}}
[[File:Pilots of No. 303 (Polish) Squadron RAF with one of their Hawker Hurricanes, October 1940. CH1535.jpg|thumb|Pilots of the [[No. 303 Polish Fighter Squadron|No. 303 ''"Kościuszko"'' Polish Fighter Squadron]] during the [[Battle of Britain]]]]

The [[Invasion of Poland]] on 1 September 1939, started the war in Europe, and the United Kingdom and France declared war on Germany on 3 September. Poland fielded the third biggest army among the European Allies, after the Soviet Union and United Kingdom, but before France.<ref>{{cite web |url=http://www.wojsko-polskie.pl/articles/view/2339 |title=Military contribution of Poland to World War II – Wojsko Polskie – Departament Wychowania i Promocji Obronności |publisher=Wojsko-polskie.pl |access-date=15 May 2010 |url-status=dead |archive-url=https://web.archive.org/web/20090606015541/http://www.wojsko-polskie.pl/articles/view/2339 |archive-date=6 June 2009}}</ref>

Polish Army suffered a series of defeats in the first days of the invasion. The Soviet Union unilaterally considered the flight to Romania of President [[Ignacy Mościcki]] and Marshal [[Edward Rydz-Śmigły]] on 17 September as evidence of ''[[debellatio]]'' causing the extinction of the Polish state, and consequently declared itself allowed to invade Poland starting from the same day.<ref>[[q:Polish September Campaign|Molotov declaration of 17 September 1939]]</ref> However, the [[Red Army]] had invaded the [[Second Polish Republic]] several hours before the Polish president fled to Romania. The Soviets invaded on 17 September at 3 a.m.,<ref>{{cite web|url=http://www.rmf24.pl/fakty/polska/news-73-rocznica-sowieckiej-napasci-na-polske,nId,635347|title=73. rocznica sowieckiej napaści na Polskę|date=17 September 2012|work=rmf24.pl}}</ref> while president Mościcki crossed the Polish-Romanian border at 21:45 on the same day.<ref>{{cite web|url=http://www.spala.info.pl/prezydentmoscicki3.php |title=Prezydent Ignacy Mościcki cz 3 prof. dr hab. Andrzej Garlicki Uniwersytet Warszawski |access-date=31 January 2013 |archive-url=https://web.archive.org/web/20090105201533/http://www.spala.info.pl/prezydentmoscicki3.php |archive-date=5 January 2009}}.</ref>

The Polish military continued to fight against both the Germans and the Soviets, and the last major battle of the war, the [[Battle of Kock (1939)|Battle of Kock]], ended at 1 a.m. on 6 October 1939 with the Independent Operational Group "Polesie", a field army, surrendering due to lack of ammunition. The country never officially surrendered to [[Nazi Germany]], nor to the Soviet Union, and continued the war effort under the [[Polish government-in-exile]].

[[File:Zdzisław de Ville.jpg|thumb|upright|Polish partisan of the [[Home Army]] (AK), "[[Jędrusie]]" unit, holding a [[Browning wz.1928]] light machine gun]]

The formation of the [[Polish Armed Forces in the West|Polish armed forces]] in France began as early as September 1939. By June 1940, their numbers had reached 85,000 soldiers.{{sfn|Zuziak|2003|p=240}} These forces took part in the [[Norwegian campaign]] and the [[Battle of France]]. After the defeat of France, the reconstitution of the Polish army had to start from scratch. Polish pilots played a key role in the [[Battle of Britain]], separate Polish units took part in the [[North African Campaign]]. After the conclusion of the [[Sikorski–Mayski agreement|Polish-Soviet agreement]] on July 30, 1941, the formation of the Polish army in the USSR (II Corps) also began.{{sfn|Zuziak|2003|p=241}} The II Corps, numbering 83,000 along with civilians, began to be evacuated from the USSR in mid-1942.{{sfn|Zuziak|2003|p=242}} It later took part in the [[Italian campaign (World War II)|fighting in Italy]].

After breaking off relations with the Polish government, the Soviet Union began forming its own Polish communist government and its armed forces in mid-1943, from which the [[First Polish Army (1944–1945)|1st Polish Army]], under [[Zygmunt Berling]], was formed on March 16, 1944.{{sfn|Weinberg|1994|pp=468, 733}} That army was fighting on the [[Eastern Front (World War II)|eastern front]], alongside the Soviet forces, including the [[Battle of Berlin]], the closing battle of the European theater of war.

The [[Home Army]], loyal to the London-based government and the largest underground force in Europe, as well other smaller resistance organizations in occupied Poland provided intelligence to the Allies and led to uncovering of [[Nazi war crimes]] (i.e., [[death camp]]s).

=== Saudi Arabia ===
Saudi Arabia severed diplomatic contacts with Germany on 11 September 1939, and with Japan in October 1941. The Saudis provided the Allies with large supplies of oil. Diplomatic relations with the United States were established in 1943. [[Ibn Saud of Saudi Arabia|King Abdul Aziz Al-Saud]] was a personal friend of Franklin D. Roosevelt. The Americans were then allowed to build an air force base near [[Dhahran]].<ref>{{Cite book |author=Jan Romein |title=The Asian Century: A History of Modern Nationalism in Asia |date=1962 |publisher=University of California Press |page=382}}</ref> Saudi Arabia declared war on Germany and Japan in 1945.<ref>{{Cite book |last=Axelrod |first=Alan |url=https://books.google.com/books?id=LbWFgjW6KX8C&dq=saudi+war+germany+28+february+japan+april&pg=PA269 |title=Encyclopedia of World War II |date=2007 |publisher=H W Fowler |isbn=978-0-8160-6022-1 |language=en}}</ref>

===South Africa===
{{Further|Military history of South Africa during World War II}}

South Africa was a sovereign Dominion under the [[Monarchy of South Africa|South African monarchy]], as per the Statute of Westminster 1931. South Africa held authority over the mandate of [[South-West Africa]]. Due to significant pro-German feeling and the presence of fascist sympathizers within the [[Afrikaner nationalism|Afrikaner nationalist]] movement (such as the [[Greyshirts|Grey Shirts]] and the [[Ossewabrandwag]]), South Africa's entry into the war was politically divisive.<ref>{{Cite book |last=Clark |first=Nancy L. |url=https://www.worldcat.org/oclc/883649263 |title=South Africa : the rise and fall of apartheid |date=2016 |others=William H. Worger |isbn=978-1-138-12444-8 |edition=Third |location=Abingdon, Oxon |oclc=883649263}}</ref> Initially the government of [[J. B. M. Hertzog#Fourth government (1938-1939)|J. B. M. Hertzog]] tried to maintain official neutrality after the outbreak of war. This caused a revolt by the governing [[United Party (South Africa)|United Party]] caucus which voted against Hertzog's position on the war and resulted in Hertzog's coalition partner, [[Jan Smuts]], forming a new government and becoming prime minister. Smuts was then able to lead the country into war on the side of the Allies.<ref>{{Cite web |date=2024-03-30 |title=J.B.M. Hertzog {{!}} South African Prime Minister & Nationalist Leader {{!}} Britannica |url=https://www.britannica.com/biography/J-B-M-Hertzog |access-date=2024-04-03 |website=www.britannica.com |language=en}}</ref>

Around 334,000 South Africans volunteered to fight in the war with 11,023 recorded wartime deaths.<ref>"Commonwealth War Graves Commission". cwgc.org. 1 March 2007. http://www.cwgc.org/</ref>

===Yugoslavia===
{{Main|World War II in Yugoslavia}}
[[File:Nemacki zarobljenici u Uzicu 1941.JPG|thumb|Partisans and Chetniks escorting captured Germans through [[Užice]], autumn 1941]]

[[Kingdom of Yugoslavia|Yugoslavia]] entered the war on the Allied side after [[Invasion of Yugoslavia|the invasion of Axis powers]] on 6 April 1941. The [[Royal Yugoslav Army]] was thoroughly defeated in less than two weeks and the country was occupied starting on 18 April. The Italian-backed Croatian fascist leader [[Ante Pavelić]] declared the [[Independent State of Croatia]] before the invasion was over. [[Peter II of Yugoslavia|King Peter II]] and much of the Yugoslavian government had left the country. In the [[United Kingdom]], they joined numerous other governments in exile from Nazi-occupied Europe. Beginning with the [[June 1941 uprising in eastern Herzegovina|uprising in Herzegovina in June 1941]], there was continuous anti-Axis resistance in Yugoslavia until the end of the war.

====Resistance factions====
[[File:Tito-Churchill.jpg|thumb|upright|Partisan leader Marshal [[Josip Broz Tito]] with [[Winston Churchill]] in 1944]]

Before the end of 1941, the anti-Axis resistance movement split between the royalist [[Chetniks]] and the communist [[Yugoslav Partisans]] of [[Josip Broz Tito]] who fought both against each other during the war and against the occupying forces. The Yugoslav Partisans managed to put up considerable resistance to the Axis occupation, forming various liberated territories during the war. In August 1943, there were over 30 Axis divisions on the territory of Yugoslavia, not including the forces of the [[Independent State of Croatia|Croatian puppet state]] and other quisling formations.<ref>{{cite web|url = https://znaci.org/00001/3.htm|author= Basil Davidson|title=Partisan Picture |access-date = 11 July 2014}}</ref> In 1944, the leading Allied powers persuaded Tito's Yugoslav Partisans and the royalist Yugoslav government led by Prime Minister [[Ivan Šubašić]] to sign the [[Treaty of Vis]] that created the [[Democratic Federal Yugoslavia]].

=====Partisans=====
{{Main|Yugoslav Partisans}}
The Partisans were a major Yugoslav resistance movement against the Axis occupation and partition of Yugoslavia. Initially, the Partisans were in rivalry with the Chetniks over control of the resistance movement. However, the Partisans were recognized by both the Eastern and Western Allies as the primary resistance movement in 1943. After that, their strength increased rapidly, from 100,000 at the beginning of 1943 to over 648,000 in September 1944. In 1945 they were transformed into the [[Yugoslav People's Army|Yugoslav army]], organized in four field armies with 800,000<ref>{{cite book|title = Balkan Idols: Religion and Nationalism in Yugoslav States|last = Perica|first = Vjekoslav|publisher = Oxford University Press|year = 2004|isbn = 0-19-517429-1|page = 96}}</ref> fighters.

=====Chetniks=====
{{Main|Chetniks}}
[[File:General Mihailovic with US Officers.jpg|thumb|Chetniks leader [[Draža Mihailović|General Mihailovic]] with members of the U.S. military mission, [[Operation Halyard]], 1944]]

The Chetniks, the short name given to the movement titled the ''Yugoslav Army of the Fatherland'', were initially a major Allied Yugoslav resistance movement. However, due to their royalist and anti-communist views, Chetniks were considered to have begun collaborating with the Axis as a tactical move to focus on destroying their Partisan rivals. The Chetniks presented themselves as a Yugoslav movement, but were primarily a [[Serbs|Serb]] movement. They reached their peak in 1943 with 93,000 fighters.<ref>{{cite book|title = Kontrarevolucija u Srbiji – Kvislinška uprava 1941–1944 (Volume 1, in Serbo-Croatian)|last = Borković|first = Milan|publisher = Sloboda|year = 1979|page = 9}}</ref> Their major contribution was [[Operation Halyard]] in 1944. In collaboration with the [[Office of Strategic Services|OSS]], 413 Allied airmen shot down over Yugoslavia were rescued and evacuated.

==Client and occupied states==

===British===
====Egypt====
{{Main|Military history of Egypt during World War II|Anglo-Egyptian treaty of 1936}}
The [[Kingdom of Egypt]] was nominally sovereign since 1922 but effectively remained in the British sphere of influence; the [[British Mediterranean Fleet]] was stationed in [[Alexandria]] while British Army forces were based in the Suez Canal zone. Egypt was a neutral country for most of World War II, but the [[Anglo-Egyptian treaty of 1936]] permitted British forces in Egypt to defend the [[Suez Canal]]. The United Kingdom controlled Egypt and used it as a major base for Allied operations throughout the region, especially the battles in North Africa against Italy and Germany. Its highest priorities were control of the Eastern Mediterranean, and especially keeping the Suez Canal open for merchant ships and for military connections with India and Australia.<ref>Steve Morewood, '' The British Defence of Egypt, 1935–40: Conflict and Crisis in the Eastern Mediterranean'' (2008).</ref>{{page needed|date=February 2021}}

Egypt faced an Axis campaign led by Italian and German forces during the war. British frustration over [[Farouk of Egypt|King Farouk]]'s reign over Egypt resulted in the [[Abdeen Palace incident of 1942]] where British Army forces surrounded the royal palace and demanded a new government be established, nearly forcing the abdication of Farouk until he submitted to British demands. The Kingdom of Egypt joined the United Nations on 24 February 1945.<ref name="Martin">{{cite book | url=https://books.google.com/books?id=jCQ7AwAAQBAJ&pg=PA8 | title=World War II: The Book of Lists | publisher=The History Press | author=Martin, Chris | year=2011 | location=Stroud | pages=8–11 | isbn=978-0-7524-6704-7}}</ref>

====India (British Raj)====
{{Further|India in World War II|Indian Army during World War II}}

At the outbreak of World War II, the [[British Indian Army]] numbered 205,000 men. Later during World War II, the Indian Army became the largest all-volunteer force in history, rising to over 2.5&nbsp;million men in size.<ref>{{cite web|url=http://www.cwgc.org/admin/files/cwgc_india.pdf |title=Commonwealth War Graves Commission Report on India 2007–2008 |access-date=7 September 2009 |publisher=[[Commonwealth War Graves Commission]] |url-status=dead |archive-url=https://web.archive.org/web/20100618081321/http://www.cwgc.org/admin/files/cwgc_india.pdf |archive-date=18 June 2010 }}</ref> These forces included tank, artillery and airborne forces.

Indian soldiers earned 30 Victoria Crosses during the Second World War. During the war, India suffered more civilian casualties than the United Kingdom, with the [[Bengal famine of 1943]] estimated to have killed at least 2{{ndash}}3&nbsp;million people.<ref>{{cite web|last=Devereux |first= Stephen |title= Famine in the twentieth century |volume= IDS Working Paper 105|location= Brighton |publisher= Institute of Development Studies |year= 2000 |url=http://www.eldis.org/vfile/upload/1/document/0708/DOC7538.pdf |archive-url=https://web.archive.org/web/20170516151220/http://www.eldis.org/vfile/upload/1/document/0708/DOC7538.pdf |url-status=dead |archive-date=16 May 2017 |page=6}}</ref> In addition, India suffered 87,000 military casualties, more than any Crown colony but fewer than the United Kingdom, which suffered 382,000 military casualties.

==== Burma ====
Burma was a British colony at the start of World War II. It was later invaded by Japanese forces and that contributed to the Bengal Famine of 1943. For the native Burmese, it was an uprising against colonial rule, so some fought on the Japanese's side, but most minorities fought on the Allies side.<ref>{{Cite web|title=Burma and World War II|url=http://www.culturalsurvival.org/publications/cultural-survival-quarterly/burma-and-world-war-ii|access-date=29 March 2021|website=www.culturalsurvival.org|date=4 March 2021 |language=en}}</ref> Burma also contributed resources such as rice and rubber.

===Soviet sphere===

====Bulgaria====
{{Main|Military history of Bulgaria during World War II}}

After a period of neutrality, [[Kingdom of Bulgaria|Bulgaria]] joined the Axis powers from 1941 to 1944. The Orthodox Church and others convinced King Boris to not allow the Bulgarian Jews to be exported to concentration camps. The king died shortly afterwards, suspected of being poisoned after a visit to Germany. Bulgaria abandoned the Axis and joined the Allies when the Soviet Union invaded, offering no resistance to the incoming forces. Bulgarian troops then fought alongside Soviet Army in Yugoslavia, Hungary and Austria. In the 1947 peace treaties, Bulgaria gained a small area near the Black Sea from Romania, making it the only former German ally to gain territory from WWII.

====Central Asian and Caucasian Republics====
Among the Soviet forces during World War II, millions of troops were from the [[Soviet Central Asia]]n Republics. They included 1,433,230 soldiers from [[Uzbekistan]],<ref>{{cite book |last1=Adle |first1=Chahryar |title=History of Civilizations of Central Asia: Towards the contemporary period : from the mid-nineteenth to the end of the twentieth century |date=2005 |publisher=[[UNESCO]] |isbn=9789231039850 |page=232 |url=https://books.google.com/books?id=XPfcfF8LRWQC&pg=PA232}}</ref> more than 1{{nbsp}}million from [[Kazakhstan]],<ref>{{cite book |last1=Robbins |first1=Christopher |title=In Search of Kazakhstan: The Land that Disappeared |date=2012 |publisher=[[Profile Books]] |isbn=9781847653567 |page=47 |url=https://books.google.com/books?id=b4tGrZsuvGkC&pg=PT47}}</ref> and more than 700,000 from [[Azerbaijan]],<ref>{{cite web |title=Azerbaijan |url=http://un.mfa.gov.az/news/4/3086 |website=Permanent Mission of the Republic of Azerbaijan to the United Nations |date=9 May 2016 |access-date=7 June 2019}}</ref> among other Central Asian Republics.

====Mongolia====
{{Main|Mongolia in World War II}}

[[Mongolian People's Republic|Mongolia]] fought against Japan during the [[Battles of Khalkhin Gol]] in 1939 and the [[Soviet–Japanese War]] in August 1945 to protect its independence and to liberate [[Southern Mongolia (region)|Southern Mongolia]] from Japan and China. Mongolia had been in the Soviet sphere of influence since the 1920s.

====Poland====
{{Main|Polish Armed Forces in the East}}

By 1944, Poland entered the Soviet sphere of influence with the establishment of [[Władysław Gomułka]]'s communist regime. Polish forces fought alongside Soviet forces against Germany.

====Romania====
{{Main|Romania in World War II|King Michael's Coup}}
[[File:Romanian soldiers in Transilvania 1944.jpg|thumb|Romanian soldiers in Transylvania, September–October 1944]]

[[Kingdom of Romania|Romania]] had initially been a member of the Axis powers but switched allegiance upon facing invasion by the [[Soviet Union]]. In a radio broadcast to the Romanian people and army on the night of 23 August 1944 [[Michael I of Romania|King Michael]] issued a cease-fire,<ref name="Library">{{cite web|url=http://countrystudies.us/romania/23.htm|title=Romania – Armistice Negotiations and Soviet Occupation|work=Country Studies US }}</ref> proclaimed Romania's loyalty to the Allies, announced the acceptance of an armistice (to be signed on 12 September)<ref>{{in lang|ro}} Delia Radu, [http://www.bbc.co.uk/romanian/news/story/2008/08/080801_serial_antonescu_episod3.shtml "Serialul 'Ion Antonescu şi asumarea istoriei' (3)"], [[BBC]] Romanian edition, 1 August 2008</ref> offered by the [[Soviet Union]], the [[United Kingdom]], the [[United States]], and declared war on Germany.<ref>{{in lang|ro}} [http://www.curierulnational.ro/Specializat/2004-08-07/"Dictatura+a+luat+sfarsit+si+cu+ea+inceteaza+toate+asupririle" ''"The Dictatorship Has Ended and along with It All Oppression" – From The Proclamation to The Nation of King Michael I on The Night of August 23 1944''] {{Webarchive|url=https://web.archive.org/web/20131202222039/http://www.curierulnational.ro/Specializat/2004-08-07/ |date=2 December 2013 }}, ''[[Curierul Naţional]]'', 7 August 2004</ref> The coup accelerated the [[Second Jassy–Kishinev Offensive|Red Army's advance into Romania]], but did not avert a rapid Soviet occupation and capture of about 130,000 Romanian soldiers, who were transported to the Soviet Union where many perished in prison camps.

The armistice was signed three weeks later on 12 September 1944, on terms virtually dictated by the Soviet Union.<ref name="Library" /> Under the terms of the armistice, Romania announced its unconditional surrender<ref>[https://www.nytimes.com/1944/08/24/archives/break-in-balkans-king-proclaims-nations-surrender-and-wish-to-help.html?scp=1 ''"King Proclaims Nation's Surrender and Wish to Help Allies"''], ''[[The New York Times]]'', 24 August 1944</ref> to the USSR and was placed under the occupation of the Allied forces with the Soviet Union as their representative, in control of the media, communication, post, and civil administration behind the front.<ref name="Library" />

Romanian troops then fought alongside the Soviet Army until the end of the war, reaching as far as [[Slovak Republic (1939–1945)|Slovakia]] and [[Nazi Germany|Germany]].

====Tuva====
{{Main|Tuva in World War II}}
The [[Tuvan People's Republic]] was a partially recognized state founded from the former Tuvan protectorate of Imperial Russia. It was a client state of the Soviet Union and was annexed into the Soviet Union in 1944.

==Co-belligerent states==

===Finland===
{{main|Lapland War}}
This Lapland War saw fighting between [[Finland in World War II|Finland]] and Germany – from September to November 1944 – in Finland's northernmost region, [[Lapland (Finland)|Lapland]]. Though the Finns and Germans had been fighting together against the Soviets since 1941 during the [[Continuation War]] (1941–44), peace negotiations between Finland and the Allies had been conducted intermittently during 1943–1944.{{sfn|Reiter|2009|p=|pp=134–137}} The [[Moscow Armistice]], signed in September 1944, demanded that Finland break diplomatic ties with Germany and expel or disarm German soldiers remaining in Finland. The ''[[Wehrmacht]]'' had anticipated this and planned an organised [[withdrawal (military)|withdrawal]] to [[German occupation of Norway|Nazi-occupied Norway]]. The Finns escalated the situation into warfare on 28 September after Soviet pressure to adhere to the armistice. The [[Finnish Army]] was required to push Wehrmacht troops out of its territory. After minor battles, the war came to an end in November 1944, when the Wehrmacht troops had reached Norway or the border area. The last Wehrmacht soldiers left Finland in April 1945.

The Finns considered the war a separate conflict because hostilities with other nations had ceased after the Continuation War. Soviet involvement in the war amounted to monitoring Finnish operations, minor air support and entering northeast Lapland during the [[Petsamo–Kirkenes Offensive]]. The military impact was relatively limited with both sides sustaining around 4,000 in total casualties, though the Germans' delaying [[scorched earth]] and [[land mine]] strategies devastated Finnish Lapland. Finland upheld its obligations under the Moscow Armistice, but it remained formally at war with the Soviet Union and UK until ratification of the [[Paris Peace Treaties, 1947]].

===Italy===
{{Further|Italian Civil War|Italian Co-Belligerent Army|Italian resistance movement|Kingdom of the South}}
[[File:Mussolini e Petacci a Piazzale Loreto, 1945.jpg|thumb|The dead bodies of Benito Mussolini, his mistress [[Clara Petacci]], and several Fascist leaders, hanging for public display after they were executed by Italian partisans in 1945]]

[[Kingdom of Italy|Italy]] initially had been a leading member of the Axis powers. However, after facing multiple military losses, including the loss of [[Italian Empire|all of Italy's colonies]] to advancing Allied forces, ''[[Duce]]'' [[Benito Mussolini]] was deposed and arrested in July 1943 by order of [[King of Italy|King]] [[Victor Emmanuel III]] of Italy in co-operation with members of the [[Grand Council of Fascism]] who viewed Mussolini as having led Italy to ruin by allying with Germany in the war. Victor Emmanuel III dismantled the remaining apparatus of the [[Italian Fascism|Fascist]] regime and appointed [[Field Marshal]] [[Pietro Badoglio]] as [[Prime Minister of Italy]]. On 8 September 1943, Italy signed the [[Armistice of Cassibile]] with the Allies, ending Italy's war with the Allies and ending Italy's participation with the Axis powers. Expecting immediate German retaliation, Victor Emmanuel III and the Italian government relocated to southern Italy under Allied control. Germany viewed the Italian government's actions as an act of betrayal, and German forces immediately occupied all Italian territories outside of Allied control,<ref>{{cite book|author1=Josef Becker|author2=Franz Knipping|title=Great Britain, France, Italy and Germany in a Postwar World, 1945–1950|url=https://books.google.com/books?id=_3ck4Sw57nEC&pg=PA506|year=1986|publisher=Walter de Gruyter|pages=506–7|isbn=9783110863918}}</ref> in some cases even [[Massacre of the Acqui Division|massacring]] Italian troops.

Italy became a co-belligerent of the Allies, and the [[Italian Co-Belligerent Army]] was created to fight against the German occupation of Northern Italy, where German paratroopers [[Gran Sasso raid|rescued Mussolini from arrest]] and he was placed in charge of a German puppet state known as the [[Italian Social Republic]] (RSI). Italy [[Italian Civil War|descended into civil war until the end of hostilities]] after his deposition and arrest, with Fascists loyal to him allying with German forces and helping them against the Italian armistice government and [[Italian resistance movement|partisans]].<ref name="Morgan2007">{{cite book|first=Philip|last=Morgan|title=The Fall of Mussolini: Italy, the Italians, and the Second World War|url=https://books.google.com/books?id=-UttMMRXi9AC&pg=PT194|year=2007|publisher=Oxford UP|pages=194–85|isbn=9780191578755}}</ref>

== Legacy ==
{{See also|Aftermath of World War II}}

===Charter of the United Nations===
{{Main|Charter of the United Nations}}The [[Declaration by United Nations]] on 1 January 1942, signed by the [[Four Policemen]] – the United States, United Kingdom, Soviet Union and China – and 22 other nations laid the groundwork for the future of the [[United Nations]].<ref>Douglas Brinkley, ''FDR & the Making of the U.N.''</ref><ref>{{Cite book|last=Ninkovich|first=Frank|title=The Wilsonian Century: US Foreign Policy since 1900|publisher=Chicago University Press|year=1999|location=Chicago|pages=137}}</ref>

At the [[Potsdam Conference]] of July–August 1945, Roosevelt's successor, [[Harry&nbsp;S. Truman]], proposed that the foreign ministers of China, France, the Soviet Union, the United Kingdom, and the United States "should draft the peace treaties and boundary settlements of Europe", which led to the creation of the [[Council of Foreign Ministers]] of the "Big Five", and soon thereafter the establishment of those states as the [[Permanent members of the United Nations Security Council|permanent members of the UNSC]].<ref name="CHURCHILL-TRIUMPH-TRAGEDY-PG561">{{cite book|last=Churchill|first=Winston S.|title=The Second World War, Volume VI: Triumph and Tragedy|publisher=[[Houghton-Mifflin Company]]|year=1981|page=561|orig-year=1953}}</ref>

The Charter of the United Nations was agreed to during the war at the [[United Nations Conference on International Organization]], held between April and July 1945. The Charter was signed by 50 states on 26 June (Poland had its place reserved and later became the 51st "original" signatory),{{citation needed|date=May 2014}} and was [[History of the United Nations#Establishment|formally ratified]] shortly after the war on 24 October 1945. In 1944, the United Nations was formulated and negotiated among the delegations from the Soviet Union, the United Kingdom, the United States and China at the [[Dumbarton Oaks Conference]]<ref>{{cite book|last=Bohlen|first=C.E.|title=Witness to History, 1929–1969|url=https://archive.org/details/witnesstohistory00bohl|url-access=registration|year=1973|location=New York|page=[https://archive.org/details/witnesstohistory00bohl/page/159 159]|publisher=New York, Norton|isbn=9780393074765}}</ref><ref>{{cite video|year =1944| title =Video: Allies Study Post-War Security Etc. (1944)|url =https://archive.org/details/gov.archives.arc.39024| publisher =[[Universal Newsreel]]| access-date =28 November 2014}}</ref> where the formation and the [[Permanent members of the United Nations Security Council|permanent seats]] (for the "Big Five", China, France, the UK, US, and USSR) of the [[United Nations Security Council]] were decided. The Security Council met for the first time in the immediate aftermath of war on 17 January 1946.<ref name="UNSC-FIRST-MEETING">United Nations Security Council: Official Records: First Year, First Series, First Meeting</ref>

These are the original 51 signatories (UNSC permanent members are asterisked):

{{div col|colwidth=18em}}
* {{flagicon|Argentina}} [[Argentina|Argentine Republic]]
* {{flagicon|Australia}} [[Australia|Commonwealth of Australia]]
* {{flagicon|Belgium}} [[Belgium|Kingdom of Belgium]]
* {{flagdeco|Bolivia|state}} [[History of Bolivia (1920–1964)#Prelude to the National Revolution, 1935–52|Republic of Bolivia]]
* {{flagicon|Vargas Era|1930}} [[Vargas Era|United States of Brazil]]
* {{flagicon|Byelorussian Soviet Socialist Republic|1937}} [[Byelorussian Soviet Socialist Republic]]
* {{flagicon|Canada|1921}} [[Canada|Dominion of Canada]]
* {{flagicon|Chile}} [[Presidential Republic (1925–1973)|Republic of Chile]]
* {{flagicon|Republic of China (1912–1949)}} [[Republic of China (1912–1949)|Republic of China]]*
* {{flagicon|Colombia|1861}} [[Colombia|Republic of Colombia]]
* {{flagicon|Costa Rica}} [[Costa Rica|Republic of Costa Rica]]
* {{flagicon|Cuba|1902}} [[Republic of Cuba (1902–59)|Republic of Cuba]]
* {{flagicon|Czechoslovakia}} [[Czechoslovakia|Czechoslovak Republic]]
* {{flagicon|Denmark}} [[Denmark|Kingdom of Denmark]]
* {{flagicon|Dominican Republic}} [[Dominican Republic]]
* {{flagicon|Ecuador|1900}} [[Ecuador|Republic of Ecuador]]
* {{flagicon|Kingdom of Egypt}} [[Kingdom of Egypt]]
* {{flagicon|El Salvador}} [[El Salvador|Republic of El Salvador]]
* {{flagicon|Ethiopian Empire}} [[Ethiopian Empire]]
* {{flagicon|Provisional Government of the French Republic}} [[Provisional Government of the French Republic|French Republic]]*
* {{flagicon|Kingdom of Greece|state}} [[Kingdom of Greece]]
* {{flagicon|Guatemala}} [[Guatemala|Republic of Guatemala]]
* {{flagicon|Haiti|1859}} [[Republic of Haiti (1859–1957)|Republic of Haiti]]
* {{flagicon|Honduras|1866}} [[Honduras|Republic of Honduras]]
* {{flagicon|British Raj}} [[British Raj]]
* {{flagicon|Pahlavi Iran|1933}} [[Pahlavi Iran|Imperial State of Iran]]
* {{flagicon|Kingdom of Iraq}} [[Kingdom of Iraq]]
* {{flagicon|Lebanon}} [[Lebanon|Lebanese Republic]]
* {{flagicon|Liberia}} [[Liberia|Republic of Liberia]]
* {{flagicon|Luxembourg}} [[Luxembourg|Grand Duchy of Luxembourg]]
* {{flagicon|Mexico|1934}} [[Mexico|United Mexican States]]
* {{flagicon|Netherlands}} [[Kingdom of the Netherlands]]
* {{flagicon|Dominion of New Zealand}} [[Dominion of New Zealand]]
* {{flagicon|Nicaragua|1908}} [[Nicaragua|Republic of Nicaragua]]
* {{flagicon|Norway}} [[Norway|Kingdom of Norway]]
* {{flagicon|Panama}} [[Panama|Republic of Panama]]
* {{flagicon|Paraguay|1842}} [[Paraguay|Republic of Paraguay]]
* {{flagicon|Peru|1884}} [[Peru|Republic of Peru]]
* {{flagicon|Philippines|1936}} [[Commonwealth of the Philippines]]
* {{flagicon|Provisional Government of National Unity}} [[Provisional Government of National Unity|Republic of Poland]]
* {{flagicon|Saudi Arabia|1938}} [[Saudi Arabia|Kingdom of Saudi Arabia]]
* {{flagicon|Union of South Africa}} [[Union of South Africa]]
* {{flagicon|Syria|1932}} [[Mandatory Syrian Republic|Syrian Republic]]
* {{flagicon|Turkey}} [[Turkey|Republic of Turkey]]
* {{flagicon|Ukrainian Soviet Socialist Republic|1937}} [[Ukrainian Soviet Socialist Republic]]
* {{flagicon|Soviet Union|1936}} [[Soviet Union|Union of Soviet Socialist Republics]]*
* {{flagicon|United Kingdom}} [[United Kingdom|United Kingdom of Great Britain and Northern Ireland]]*
* {{flagicon|United States|1912}} [[United States|United States of America]]*
* {{flagicon|Uruguay}} [[Uruguay|Oriental Republic of Uruguay]]
* {{flagicon|Venezuela|1930}} [[United States of Venezuela]]
* {{flagicon|Democratic Federal Yugoslavia}} [[Democratic Federal Yugoslavia]]
{{div col end}}

=== Cold War ===
{{Main|Cold War}}

Despite the successful creation of the United Nations, the alliance of the Soviet Union with the United States and [[Anglo-Soviet Treaty of 1942|with the United Kingdom]] ultimately broke down and evolved into the [[Cold War]], which took place over the following half-century.<ref name=":9" /><ref name=":4" />

==Summary table==
[[File:Freedom shall prevail! - DPLA - b0c9b437727d3a683688c8a4860772b5.jpg|thumb|Poster with [[V sign|V for Victory]]]]
The Big Three:
* {{flagcountry|United Kingdom}} ([[United Kingdom declaration of war on Germany (1939)|from September 1939]])
* {{flagcountry|Soviet Union|1936}} ([[Operation Barbarossa|from June 1941]])
* {{flagcountry|United States|1912}} ([[Attack on Pearl Harbor|from December 1941]])

Allied combatants with governments in exile:
* {{flagdeco|Free French}} [[Free France]]<ref group=note name=FFF/>
* {{flagcountry|Polish government-in-exile}}<ref group=note name=PL/>
* {{flagcountry|Czechoslovak government-in-exile}}<ref group=note name=CS/>
* {{flagcountry|Belgian government in exile}}
* {{flagcountry|Luxembourg government in exile}}
* {{flagcountry|Dutch government-in-exile}}
* {{flagdeco|Norway}} [[Nygaardsvold's Cabinet|Norway]]
* {{flagcountry|Greek government-in-exile|state}}
* {{flagdeco|Kingdom of Yugoslavia}} [[Yugoslav government-in-exile|Yugoslavia]]
* {{flagdeco|Ethiopian Empire}} [[Ethiopian Empire in exile|Ethiopia]]<ref group=note name=EE/>
* {{flagicon image|War_Flag_of_the_Philippines_(1936–1985,_1986–1998).svg}} [[Government in exile of the Commonwealth of the Philippines|Philippines]]

Other Allied combatant states:
* {{flagcountry|Republic of China (1912-1949)|1940}}<ref group=note name=RoC/>
* {{flagcountry|Canada|1921}}
* {{flagcountry|Australia}}
* {{flagcountry|Dominion of New Zealand}}
* {{flagcountry|British Raj}}
* {{flagcountry|Union of South Africa}}
* {{flagcountry|Vargas Era|1930}}
* {{flag|Mexico|1934}}
* {{flagcountry|Mongolian People's Republic|1945}}

Co-belligerents (former Axis powers):
* {{flagicon|Kingdom of Italy}} [[Kingdom of the South|Italy]] ([[Italian Civil War|from September 1943]])
* {{flagcountry|Kingdom of Romania}} ([[King Michael's Coup|from August 1944]])
* {{flagcountry|Kingdom of Bulgaria}} ([[1944 Bulgarian coup d'état|from September 1944]])
* {{flagcountry|Finland}} ([[Lapland War|from September 1944]])

{| class="wikitable sortable" style="width:60em;"
|+Allies of World War II – Declaration by United Nations and at the San Francisco Conference
! Country !! [[Declaration by United Nations]]
![[Declarations of war during World War II|Declared war on the Axis]]!! [[United Nations Conference on International Organization|San Francisco Conference]]
|-
|{{flagicon|Argentina|1831}} [[Argentina]] || {{na}} || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Australia}} [[Australia]] || {{ya}} 1942 || {{ya}} 1939/40/42 || {{ya}}
|-
|{{flagicon|Belgium}} [[Belgian government in exile|Belgium]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Bolivia|state}} [[History of Bolivia (1920–1964)#Prelude to the National Revolution, 1935–52|Bolivia]] || {{ya}} 1943 || {{ya}} 1943 || {{ya}}
|-
|{{flagicon|Vargas Era|1930}} [[Vargas Era|Brazil]] || {{ya}} 1943 || {{ya}} 1942 || {{ya}}
|-
|{{flagicon|Cambodia|1863}} [[French protectorate of Cambodia|Cambodia]] || {{na}}
| || {{ya}}
|-
|{{flagicon|Canada|1921}} [[Canada]] || {{ya}} 1942 || {{ya}} 1939/40/41 || {{ya}}
|-
|{{flagicon|British Ceylon}} [[Dominion of Ceylon|Ceylon]] || {{na}}
| || {{ya}}
|-
|{{flagicon|Chile}} [[Presidential Republic (1925–1973)|Chile]] ||{{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Republic of China (1912–1949)}} [[Republic of China (1912–1949)|China]] ||{{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Colombia|1861}} [[Colombia]] || {{ya}} 1943 || {{ya}} 1943 || {{ya}}
|-
|{{flagicon|Costa Rica}} [[Costa Rica]] ||{{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Cuba|1902}} [[Republic of Cuba (1902–59)|Cuba]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Czechoslovak government-in-exile}} [[Czechoslovak government-in-exile|Czechoslovakia]] ||{{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Dominican Republic}} [[Third Dominican Republic|Dominican Republic]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Ecuador|1900}} [[Ecuador]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Kingdom of Egypt}} [[Kingdom of Egypt|Egypt]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|El Salvador}} [[El Salvador]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Ethiopian Empire}} [[Ethiopian Empire|Ethiopia]] || {{ya}} 1942 || {{ya}} 1942 || {{ya}}
|-
|{{flagicon|Provisional Government of the French Republic}} [[Provisional Government of the French Republic|France]] || {{ya}} 1944 || {{ya}} 1939/40/41/44 || {{ya}}
|-
|{{flagicon|Kingdom of Greece|state}} [[Greek government in exile|Greece]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|Guatemala}} [[Guatemala]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Haiti|1859}} [[Republic of Haiti (1859–1957)|Haiti]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Honduras|1866}} [[Honduras]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|British Raj}} [[British Raj|India]] (UK-appointed administration, 1858–1947) || {{ya}} 1942 || {{ya}} 1939 || {{ya}}
|-
|{{flagicon|Dutch East Indies}} [[Dutch East Indies|Indonesia]] || {{na}}
| || {{ya}}
|-
|{{flagicon|Pahlavi Iran|1933}} [[Pahlavi Iran|Iran]] || {{ya}} 1943 || {{ya}} 1943 || {{ya}}
|-
|{{flagicon|Kingdom of Iraq}} [[Kingdom of Iraq|Iraq]] || {{ya}} 1943
| || {{ya}}
|-
|{{flagicon|Kingdom of Laos}} [[French protectorate of Laos|Laos]] || {{na}}
| || {{ya}}
|-
|{{flagicon|Lebanon}} [[Lebanon]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Liberia}} [[Liberia]] || {{ya}} 1944 || {{ya}} 1943 || {{ya}}
|-
|{{flagicon|Luxembourg}} [[Luxembourg government-in-exile|Luxembourg]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|Mexico|1934}} [[Mexico]] || {{ya}} 1942 || {{ya}} 1942 || {{ya}}
|-
|{{flagicon|Netherlands}} [[Dutch government-in-exile|Netherlands]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|Dominion of New Zealand}} [[Dominion of New Zealand|New Zealand]] || {{ya}} 1942 || {{ya}} 1939/40/42 || {{ya}}
|-
|{{flagicon|Nicaragua|1908}} [[Nicaragua]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Norway}} [[Nygaardsvold's Cabinet|Norway]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|Panama}} [[Panama]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Paraguay|1842}} [[Paraguay]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Peru|1884}} [[Peru]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Philippines|1936}} [[Commonwealth of the Philippines|Philippines]] || {{ya}} 1942 || {{ya}} 1941 || {{ya}}
|-
|{{flagicon|Polish government-in-exile}} [[Polish government-in-exile|Poland]] || {{ya}} 1942 || {{ya}} 1941 || {{na}}
|-
|{{flagicon|Saudi Arabia|1938}} [[Saudi Arabia]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Union of South Africa}} [[Union of South Africa|South Africa]] || {{ya}} 1942 || {{ya}} 1939/40/41/42 || {{ya}}
|-
|{{flagicon|Soviet Union|1936}} [[Soviet Union]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|Syria|1932}} [[Mandatory Syrian Republic|Syria]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Turkey}} [[Turkey]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|United Kingdom}} [[United Kingdom]] || {{ya}} 1942 || {{ya}} 1939/41/42 || {{ya}}
|-
|{{flagicon|United States|1912}} [[United States]] || {{ya}} 1942 || {{ya}} 1941/42 || {{ya}}
|-
|{{flagicon|Uruguay}} [[Uruguay]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Venezuela|1930}} [[United States of Venezuela|Venezuela]] || {{ya}} 1945 || {{ya}} 1945 || {{ya}}
|-
|{{flagicon|Kingdom of Yugoslavia}} [[Yugoslav government-in-exile|Yugoslavia]] || {{ya}} 1942
| || {{ya}}
|-
|{{flagicon|French Indochina}} [[Nguyễn dynasty|Vietnam]] || {{na}} || {{ya}} 1941 || {{ya}}
|}

==Timeline of Allied nations entering the war==
{{Main|Declarations of war during World War II}}

The following list denotes dates on which states declared war on the Axis powers, or on which an Axis power declared war on them.

===1939===
* {{flagicon|Second Polish Republic}} [[Second Polish Republic|Poland]]: 1 September 1939<ref>Weinberg, Gerhard L. (2005) A World at Arms: A Global History of World War II (2nd ed.). Cambridge University Press. pp. 6.</ref>
* {{flagicon|French Third Republic}} [[French Third Republic|France]]: 3 September 1939<ref name="BBCbritainfrance">{{cite news | url=http://news.bbc.co.uk/onthisday/hi/dates/stories/september/3/newsid_3493000/3493279.stm | title=1939: Britain and France declare war on Germany | date=3 September 1939 | publisher=[[BBC]] | access-date=17 February 2015}}</ref>
* {{flagicon|United Kingdom}} [[United Kingdom]]: 3 September 1939<ref name="BBCbritainfrance" />
** {{flagicon|British Raj}} [[British Raj|India]]: 3 September 1939<ref name="Connelly">{{cite book | url=https://books.google.com/books?id=TzJtY1Mlu_4C&pg=PA68 | title=The IRA on Film and Television: A History | publisher=McFarland | author=Connelly, Mark | year=2012 | pages=68 | isbn=978-0-7864-8961-9}}</ref><ref>{{cite book | url=https://books.google.com/books?id=xlsrAxuWekQC&pg=PA65 | title=A World at Arms: A Global History of World War II | publisher=[[Cambridge University Press]] | author=Weinberg, Gerhard L. | year=2005 | pages=65 | isbn=978-0-521-61826-7}}</ref>
* {{flagicon|Australia}} [[Australia]]: 3 September 1939<ref name="Connelly" /><ref>{{cite book | url=https://books.google.com/books?id=gz6BI-4jl_oC&pg=PA89 | title=Australia: A Very Short Introduction | publisher=[[Oxford University Press]] | author=Morgan, Kenneth | year=2012 | location=Oxford | pages=89 | isbn=978-0-19-958993-7}}</ref>
* {{flagicon|Dominion of New Zealand}} [[Dominion of New Zealand|New Zealand]]: 3 September 1939<ref name="Connelly" /><ref>[http://www.nzhistory.net.nz/new-zealand-declares-war-on-germany New Zealand declares war on Germany], Ministry for Culture and Heritage, updated 14 October 2014</ref>
* {{flagicon|Nepal|1930}} [[Kingdom of Nepal|Nepal]]: 4 September 1939<ref>{{cite book | url=https://books.google.com/books?id=AOiZBgAAQBAJ&pg=PA89 | title=I Won't Be Home Next Summer: Flight Lieutenant R.N. Selley DFC (1917Ð1941) | publisher=30 Degrees South Publishers | author=Selley, Ron | year=2014 | location=Pinetown | pages=89 | isbn=978-1-928211-19-8 | last2=Cocks | first2=Kerrin}}</ref>
* {{flagicon|Union of South Africa}} [[Union of South Africa|South Africa]]: 6 September 1939<ref name="Martin"/>
* {{flagicon|Canada|1921}} [[Canada]]: 10 September 1939<ref name="Martin"/>
* {{flagcountry|Muscat and Oman}}: 10 September 1939

===1940===
* {{flagicon|Norway}} [[Norway]]: 8 April 1940<ref name="Martin"/>
* {{flagicon|Denmark}} [[Denmark]] 9 April 1940{{snd}}German invasion without declaration of war.<ref>{{Cite web |title=Germany invades Denmark and Norway {{!}} Anne Frank House |url=https://www.annefrank.org/en/anne-frank/the-timeline/entire-timeline/#61 |access-date=2023-09-29 |website=Anne Frank Website |language=en}}</ref>
* {{flagicon|Belgium}} [[Belgium]]: 10 May 1940{{Citation needed|date=February 2015}}
* {{flagicon|Luxembourg}} [[Luxembourg]]: 10 May 1940{{Citation needed|date=February 2015}}
* {{flagicon|Netherlands}} [[Netherlands]]: 10 May 1940{{Citation needed|date=February 2015}}
* {{flagicon|Kingdom of Greece|state}} [[Kingdom of Greece|Greece]]: 28 October 1940{{Citation needed|date=February 2015}}

===1941===
<!-- The following flags/countries represent formal declarations of war by independent states, not declarations by provisional governments, colonial regimes on behalf of colonies, or other non-independent countries. The Philippines' foreign and military affairs were controlled, ultimately by the United States during World War II, although it had an elected government that was formally represented in international forums.-->
* {{flagicon|Kingdom of Yugoslavia}} [[Kingdom of Yugoslavia|Yugoslavia]]: 6 April 1941 (Yugoslavia signed the [[Tripartite Pact]], becoming a nominal member of the Axis on 25 March; but was [[Operation 25|attacked by the Axis]] on 6 April 1941.)<ref>{{cite web|last=Sotirović|first=Vladislav B.|date=18 December 2011|script-title=sr:Кнез Павле Карађорђевић и приступање Југославије Тројном пакту|publisher=NSPM|url=http://www.nspm.rs/istina-i-pomirenje-na-ex-yu-prostorima/knez-pavle-karadjordjevic-i-pristupanje-jugoslavije-trojnom-paktu.html|language=sr}}"</ref>
<!--PLEASE NOTE: This line has been the subject of persistent misconceptions. Please check Talk:Allies of World War II#USSR (the USSR section on talk) and make sure that you are not
replicating them if you intend to edit the line. It is probably a wise idea to discuss on that page FIRST, before editing. The USSR was at war with Poland in 1939, not any other Allied country. -->[[File:Poster russian.jpg|thumb|upright|U.S. government poster showing a friendly [[Red Army|Soviet soldier]], 1942]]
* {{flagicon|Soviet Union|1936}} [[Soviet Union]]: 22 June 1941;{{Citation needed|date=February 2015}} Despite membership of the Soviet Union, [[Ukrainian Soviet Socialist Republic|Ukraine]] and [[Byelorussian Soviet Socialist Republic|Belarus]] were recognized as separate fighting states by the United Kingdom and the United States at the end of the war.{{citation needed|date=February 2015}}
* {{flagicon|Panama}} [[Panama]]: 7 December 1941{{Citation needed|date=February 2015}}
* {{flagicon|United States|1912}} [[United States]]: 8 December 1941 (war declared on Japan after the [[Attack on Pearl Harbor|Pearl Harbor attack]])<ref>{{Cite news |last=Kluckhohn |first=Frank L. |date=8 December 1941 |title=U.S. Declares War, Pacific Battle Widens |pages=1 |work=[[The New York Times]] |url=https://archive.nytimes.com/www.nytimes.com/learning/general/onthisday/big/1208.html |access-date=2023-08-28 |archive-url=https://web.archive.org/web/20180903114931/https://archive.nytimes.com/www.nytimes.com/learning/general/onthisday/big/1208.html|archive-date=September 3, 2018}}</ref>
** {{flagicon|Philippines|1936}} [[Commonwealth of the Philippines|Philippines]]: 8 December 1941<ref>Dear and Foot, ''Oxford Companion to World War II'' pp 878–9</ref>
* {{flagicon|Costa Rica}} [[Costa Rica]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|Dominican Republic}} [[Third Dominican Republic|Dominican Republic]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|El Salvador}} [[El Salvador]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|Haiti|1859}} [[Republic of Haiti (1859–1957)|Haiti]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|Honduras|1866}} [[Honduras]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|Nicaragua|1908}} [[Nicaragua]]: 8 December 1941<ref name="Martin"/>
* {{flagicon|Republic of China (1912–1949)}} [[Republic of China (1912–1949)|China]]: 9 December 1941<ref name="Martin"/> (at war with Japan since 1937)<ref>{{cite news | url=http://edition.cnn.com/2015/08/31/opinions/china-wwii-forgotten-ally-rana-mitter/index.html | title=Forgotten ally? China's unsung role in World War II | author=Rana Mitter | journal=[[CNN]] }}</ref>
* {{flagicon|Cuba|1902}} [[Republic of Cuba (1902–1959)|Cuba]]: 9 December 1941<ref name="Martin"/>
* {{flagicon|Guatemala}} [[Guatemala]]: 9 December 1941<ref name="Martin"/>
* {{flagicon|United States|1912}} [[United States]]: 11 December 1941 (war declared on the U.S. by Germany and Italy)<ref name="Martin"/>

Provisional governments or governments-in exile that declared war against the Axis in 
===1941===
* {{flagicon|Provisional Government of the Republic of Korea}} [[Provisional Government of the Republic of Korea]]: 10 December 1941<ref name="A. Wigfall Green">{{cite book | url=https://books.google.com/books?id=gPF9CgAAQBAJ&pg=PT40 | title=The Epic of Korea | publisher=Read Books | author=A. Wigfall Green | year=2007 | page=6 | isbn=978-1-4067-0320-7}}</ref>
* {{flagicon|Czechoslovakia}} [[Czechoslovak government-in-exile|Czechoslovakia (government-in-exile)]]: 16 December 1941<ref name="Martin"/><ref>Dear and Foot, ''Oxford Companion to World War II'' pp. 279–80</ref>

===1942===
<!-- The following flags/countries denote formal declarations of war by independent states, not declarations by provisional governments, colonial regimes on behalf of colonies, or other non-independent countries. -->
* {{flagicon|Mexico|1934}} [[Mexico]]: 22 May 1942<ref name="Martin"/>
* {{flagicon|Vargas Era|1930}} [[Vargas Era|Brazil]]: 22 August 1942<ref name="Martin"/>
* {{flagicon|Ethiopian Empire}} [[Ethiopian Empire|Ethiopia]]: 14 December 1942<ref name="Martin"/>

===1943===
[[File:At War Against the Axis - UK World War II poster, 1943 (44266218).png|thumb|Flags of the Allies as of 1943, after the entry of Iraq and Bolivia]]
* {{flagicon|Kingdom of Iraq}} [[Kingdom of Iraq|Iraq]]: 16 January 1943<ref name="Martin"/>{{snd}}
* {{flagicon|Bolivia}} [[Bolivia]]: 7 April 1943{{Citation needed|date=February 2015}}
* {{flagicon|Colombia|1861}} [[Colombia]]: 26 July 1943{{Citation needed|date=February 2015}}
* {{flagicon|Pahlavi Iran|1933}} [[Pahlavi Iran|Iran]]: 9 September 1943<ref name="Martin"/>
* {{flagicon|Kingdom of Italy}} [[Kingdom of Italy|Italy]]: 10 October 1943<ref name="Martin"/>{{snd}}former Axis power; [[Italian Social Republic]] was founded in September 1943 and continued on the Axis side

===1944===
<!-- The following flags/countries denote formal declarations of war by independent states, not declarations by provisional governments, colonial regimes on behalf of colonies, or other non-independent countries. -->
* {{flagicon|Liberia}} [[Liberia]]: 27 January 1944<ref name="Martin"/>
* {{flagicon|Kingdom of Romania}} [[Kingdom of Romania|Romania]]: 25 August 1944<ref name="Martin"/>{{snd}}former Axis power
* {{flagicon|Tsardom of Bulgaria (1908–1946)}} [[Tsardom of Bulgaria (1908–1946)|Bulgaria]]: 8 September 1944<ref>''A Political Chronology of Europe'', Psychology Press, 2001, [https://books.google.com/books?id=qC7pvX2M39AC&dq=bulgaria+declared+war+1944&pg=PA45 p.45]</ref>{{snd}}former Axis power

===1945===
* {{flagicon|Ecuador|1900}} [[Ecuador]]: 2 February 1945{{Citation needed|date=February 2015}}
* {{flagicon|Paraguay|1842}} [[Paraguay]]: 7 February 1945<ref name="Martin"/>
* {{flagicon|Peru|1884}} [[Peru]]: 12 February 1945<ref>Masterson, Daniel M. and Jorge Ortiz Sotelo in Thomas M. Leonard and John F. Bratzel. eds. Latin America During World War II (Rowman & Littlefield: 2007), 226p.</ref>
* {{flagicon|Uruguay}} [[Uruguay]]: 15 February 1945{{Citation needed|date=February 2015}}
* {{flagicon|Venezuela|1930}} [[United States of Venezuela|Venezuela]]: 15 February 1945{{Citation needed|date=February 2015}}
* {{flagicon|Turkey}} [[Turkey]]: [[Turkish declaration of war on Germany and Japan|23 February 1945]]<ref name="Martin"/>
* {{flagicon|Kingdom of Egypt}} [[Kingdom of Egypt|Egypt]]: 24 February 1945<ref name="Martin"/>
* {{flagicon|Syria|1932}} [[Mandatory Syrian Republic|Syria]]: 26 February 1945<ref name="Martin"/>
* {{flagicon|Lebanon}} [[Lebanon]]: 27 February 1945<ref name="Martin"/>
* {{flagicon|Saudi Arabia|1938}} [[Saudi Arabia]]: 1 March 1945<ref name="Martin"/>
* {{flagicon|Finland}} [[Finland]]: 3 March 1945<ref name="Martin"/>{{snd}}former ally of Germany in the [[Continuation War]]. On 3 March 1945, Finland retroactively declared war on Germany from 15 September 1944.
* {{flagicon|Argentina|1831}} [[Argentina]]: 27 March 1945<ref>Decree 6945/45</ref>
* {{flagicon|Chile}} [[Presidential Republic (1925–1973)|Chile]]: 11 April 1945 declared war on Japan<ref name="Martin"/>
* {{flagicon|Kingdom of Italy}} [[Kingdom of Italy|Italy]]: On 14 July 1945 the Kingdom of Italy formally declared war on Japan<ref>{{cite web|first=Richard|last=Doody|title= Chronology of World War II Diplomacy 1939 – 1945|work=The World at War worldatwar.net|url= http://worldatwar.net/timeline/other/diplomacy39-45.html|access-date=14 August 2008}}</ref> ([[Military history of Italy during World War II|Italy and Japan after the surrender]])
* {{flagicon|Mongolian People's Republic|1945}} [[Mongolian People's Republic|Mongolia]]: August 1945 declared war on Japan

==See also==
{{Portal|History}}
* [[Allied leaders of World War II]]
* [[Allied technological cooperation during World War II]]
* [[Free World]]
* [[Military production during World War II]]
* [[World War II by country]]
* [[United Kingdom–United States relations in World War II]]
** [[Tizard Mission]]

==Notes==
{{reflist|group=note|refs=
<ref name="EE">The Ethiopian Empire was [[Second Italo-Ethiopian War|invaded]] by [[Fascist Italy|Italy]] on 3 October 1935. On 2 May 1936, Emperor [[Haile Selassie I]] fled into exile, just before the Italian occupation on 7 May. After the outbreak of World War II, the United Kingdom recognized Haile Selassie as the Emperor of Ethiopia in July 1940 and his Ethiopian exile government [[Gideon Force|cooperated with the British]] during their [[East African campaign (World War II)|invasion of Italian East Africa]] in 1941. Through the invasion Haile Selassie returned to Ethiopia on 18 January, with the liberation of the country being completed by November the same year.</ref>
<ref name="FFF">[[French Third Republic|France]] [[French declaration of war on Germany (1939)|declared war on Germany]] on 3 September 1939, two days after the German invasion of Poland. It was a member of the Allies until its defeat in the [[Battle of France|German invasion of France]] in June 1940. Unlike the other [[Government in exile|governments-in-exile]] in London, which were legitimate governments that had escaped their respective countries and continued the fight, France had [[Armistice of 22 June 1940|surrendered]] to the Axis. The "[[Free French Forces]]" were a section of the French army which refused to recognize the armistice and continued to fight with the Allies. They worked towards France being seen and treated as a major allied power, as opposed to a defeated and then liberated nation. They struggled with legitimacy vis-a-vis the German [[client state]] "[[Vichy France]]", which was the internationally recognized government of France [[Foreign relations of Vichy France|even among the Allies]]. A [[French Committee of National Liberation|National Liberation Committee]] was formed by the Free French after the gradual liberation of Vichy colonial territory, which led to the [[Case Anton|full German occupation of Vichy France]] in 1942. This started a shift in Allied policy from trying to improve relations with the Vichy regime into full support to what was now the [[Provisional Government of the French Republic]].</ref>
<ref name="RoC">China had been at [[Second Sino-Japanese War|war with Japan]] since July 1937. It declared war on Japan, Germany and Italy and joined the Allies in December 1941 after the attacks on Pearl Harbor.</ref>
<ref name="CS">[[Edvard Beneš]], president of the [[First Czechoslovak Republic]], fled the country after the 1938 [[Munich Agreement]] saw the [[Sudetenland]] region annexed by Germany. In 1939 a German sponsored [[Slovak Republic (1939–1945)|Slovak Republic]] seceded from the post-Munich [[Second Czechoslovak Republic]], providing justification for the establishment of a [[Protectorate of Bohemia and Moravia|German protectorate]] over the remaining Czech lands (the rump [[Carpatho-Ukraine|Carpathian Ruthenia]] region being annexed by Hungary). Following the outbreak of war later the same year, Beneš, in his exile, formed a Czechoslovak National Liberation Committee which after some months of negotiations regarding its legitimacy became regarded as the Czechoslovak government-in-exile by the Allies.</ref>
<ref name="PL">[[Second Polish Republic|Poland]] was allied with the United Kingdom and France, and was [[Invasion of Poland|attacked by Germany and the Soviet Union]] in 1939. The [[Polish government-in-exile|government-in-exile]] continued to fight alongside the Western Allies. It also signed the [[Sikorski-Mayski agreement|alliance]] with the Soviet Union on July 30, 1941, which was broken by the Soviets on April 25, 1943. Subsequently, the puppet, created in Moscow, [[Union of Polish Patriots]] fought against Germany and [[Polish Underground State]] alongside the Soviets.</ref>
<!--<ref group=note name=DF>The [[Kingdom of Yugoslavia]] signed the [[Tripartite Pact]], but [[Yugoslav coup d'état|a coup d'état]] staged two days after signing overthrew the government.</ref><ref group=note name=IQ>Iraq was a former co-belligerent of the Axis during the [[Anglo-Iraqi War]].</ref> -->
}}

==Sources==
{{reflist}}

===Bibliography===
* [[Norman Davies|Davies, Norman]] (2006), ''[[Europe at War 1939–1945: No Simple Victory]]''. London: Macmillan. {{ISBN|0-333-69285-3}}
* Dear, Ian C. B. and Michael Foot, eds. ''The Oxford Companion to World War II'' (2005), comprehensive encyclopedia for all countries; [https://archive.org/details/oxfordcompaniont00dear online]
* Holland R. (1981), ''Britain and the Commonwealth alliance, 1918–1939'', London: Macmillan. {{ISBN|978-0-333-27295-4}}
* Leonard, T. M. (2007). ''Latin America during World War II''. Lanham Md: Rowman & Littlefield. {{ISBN|978-1-461-63862-9}}
* [[Richard Overy|Overy, Richard]] (1997), ''Russia's War: A History of the Soviet Effort: 1941–1945''. New York: Penguin. {{ISBN|0-14-027169-4}}.
* {{cite book |last=Reiter |first=Dan |date=2009 |title=How Wars End |publisher=Princeton University Press |isbn=9781400831036}}
* Smith, Gaddis. ''American Diplomacy During the Second World War, 1941–1945'' (1965) [https://archive.org/details/in.ernet.dli.2015.118212 online]
* {{cite book |last1=Weinberg |first1=Gerhard L. |title=A World at Arms: A Global History of World War II |date=1994 |publisher=Cambridge University Press |isbn=978-0-521-44317-3 |url=https://books.google.com/books?id=AJj1glSfifgC |language=en}} Comprehensive coverage of the war with emphasis on diplomacy [https://www.amazon.com/dp/0521618266/ excerpt and text search]
* {{Cite journal |last=Zuziak |first=Janusz |date=2003 |title=Wysiłek mobilizacyjno-organizacyjny Polskich Sił Zbrojnych na Zachodzie w drugiej wojnie światowej |journal=Piotrkowskie Zeszyty Historyczne |volume=5}}

==Further reading==
* Butler, Susan. ''Roosevelt and Stalin : portrait of a partnership'' (Knopf, 2015) [https://archive.org/details/rooseveltstalinp0000butl_u1o9 online]
* Edmonds, Robin. ''The big three : Churchill, Roosevelt, and Stalin in peace & war'' (WW Norton, 1991) [https://archive.org/details/bigthreechurchil00edmo online]
* Feis, Herbert. ''Churchill-Roosevelt-Stalin: The war they waged and the peace they sought'' (1957) major scholarly study [https://archive.org/details/churchillrooseve00feis online]
* Fenby, Jonathan. ''Alliance: the inside story of how Roosevelt, Stalin and Churchill won one war and began another'' (Simon and Schuster, 2015). detailed narrative. [https://archive.org/details/allianceinsidest0000fenb_n3w0 online]
* Kimball, Warren F. ''Forged in war : Roosevelt, Churchill, and the Second World War'' (1997) [https://archive.org/details/forgedinwarroose0000kimb online]
* Lehrman, Lewis E. ''Churchill, Roosevelt & company : studies in character and statecraft'' (2017) [https://archive.org/details/churchillrooseve0000lehr online]
* {{Cite book |last=Ready |first=J. Lee |year=2012 |orig-year=1985 |title=Forgotten Allies: The Military Contribution of the Colonies, Exiled Governments, and Lesser Powers to the Allied Victory in World War II |location=Jefferson, N.C. |publisher=McFarland & Company |isbn=978-0899501178 |oclc=586670908}} Omnibus of [https://archive.org/details/forgottenalliesm0001read Volume I: ''The European Theater''] {{Registration required}} and Volume II: ''The Asian Theater''.
* Roberts, Andrew. ''Masters and commanders : how Roosevelt, Churchill, Marshall, and Alanbrooke won the war in the West'' (2018) [https://archive.org/details/masterscommander0000robe_p4m9 online]

===Primary sources===
* ''Churchill & Roosevelt : the complete correspondence'' (1984) [https://archive.org/details/churchillrooseve0001chur online]
* ''Roosevelt and Churchill : their secret wartime correspondence'' (1990) [https://archive.org/details/rooseveltchurchi0000roos_c4j6 online]
* ''Stalin's Correspondence With Churchill Attlee Roosevelt And Truman 1941–45'' (1958) [https://archive.org/details/stalinscorrespon010909mbp/page/n3/mode/2up online]

==External links==
* [http://avalon.law.yale.edu/wwii/at17.asp The Atlantic Conference: Resolution of 24 September 1941]

{{WWII history by nation}}
{{United Nations}}
{{World War II}}

{{Authority control}}

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[[Category:20th-century military alliances]]
[[Category:Military alliances involving Canada]]
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[[Category:Military alliances involving South Africa]]
[[Category:Military alliances involving France]]
[[Category:Politics of World War II]]
[[Category:History of diplomacy]]
[[Category:Military alliances involving India]]