A non-aggression pact or neutrality pact is a treaty between two or more states/countries that includes a promise by the signatories not to engage in military action against each other. Such treaties may be described by other names, such as a treaty of friendship or non-belligerency, etc.
Leeds, Ritter, Mitchell, & Long (2002) distinguish between a non-aggression pact and a neutrality pact. They posit that a non-aggression pact includes the promise not to attack the other pact signatories, whereas a neutrality pact includes a promise to avoid support of any entity that acts against the interests of any of the pact signatories. The most readily recognized example of the aforementioned entity is another country, nation-state, or sovereign organization that represents a negative consequence towards the advantages held by one or more of the signatory parties.
In the 19th century neutrality pacts have historically been used to give permission for one signatory of the pact to attack or attempt to negatively influence an entity not protected by the neutrality pact. The participants of the neutrality pact agree not to attempt to counteract an act of aggression waged by a pact signatory towards an entity not protected under the terms of the pact. Possible motivations for such acts by one or more of the pacts' signatories include a desire to take, or expand, control of, economic resources, militarily important locations, etc.
Such pacts were a popular form of international agreement in the 1920s and 1930s, but have largely fallen out of use after the Second World War. Since the implementation of a non-aggression pact necessarily depends on the good faith of the parties, the international community[who?], following the Second World War, adopted the norm of multilateral collective security agreements, such as the treaties establishing NATO, ANZUS, SEATO and Warsaw Pact.
An example of non-aggression pact is the 1939 Molotov–Ribbentrop Pact between the Soviet Union and Nazi Germany. The Pact lasted until the 1941 German invasion of the Soviet Union in Operation Barbarossa. However, such pacts may be a device for neutralising a potential military threat, enabling at least one of the signatories to free up its military resources for other purposes. For example, the Molotov–Ribbentrop Pact freed German resources from the Russian front and was the trigger for the Second World War. On the other hand, the Soviet–Japanese Neutrality Pact, signed on April 13, 1941, removed the threat from Japan in the east enabling the Soviets to move large forces from Siberia to the fight against the Germans, which had a direct bearing on the Battle of Moscow.
On 11th September 2019 Nigel Farage, as leader of the United Kingdom Brexit Party, proposed a non-aggression pact with the Conservative Party and its leader Boris Johnson for upcoming elections. It is unclear whether the association with historical pacts, particularly those of Nazi Germany, was intentional.
List of non-aggression pacts
- Treaty of London (1518)
- Soviet–Lithuanian Non-Aggression Pact (September 28, 1926)
- Greek–Romanian Non-Aggression and Arbitration Pact (March 21, 1928)
- Soviet–Afghan Non-Aggression Pact (June 24, 1931)
- Soviet–Finnish Non-Aggression Pact (January 21, 1932)
- Soviet–Latvian Non-Aggression Pact (February 5, 1932)
- Soviet–Estonian Non-Aggression Pact (May 4, 1932)
- Soviet–Polish Non-Aggression Pact (July 25, 1932)
- Soviet–Italian Non-Aggression Pact (September 2, 1933)
- Romanian–Turkish Non-Aggression Pact (October 17, 1933)
- Turkish–Yugoslav Non-Aggression Pact (November 27, 1933)
- German–Polish Non-Aggression Pact (January 26, 1934)
- Franco-Soviet Treaty of Mutual Assistance (May 2, 1935)
- Sino-Soviet Non-Aggression Pact (August 21, 1937)
- Treaty of Saadabad (June 25, 1938)
- Hungarian–Little Entente agreement (August 22, 1938)
- German–Danish Non-Aggression Pact (May 31, 1939)
- German–Estonian Non-Aggression Pact (June 7, 1939)
- German–Latvian Non-Aggression Pact (June 7, 1939)
- Molotov–Ribbentrop Pact (23 August 1939)
- British–Thai Non-Aggression Pact (June 12, 1940)
- Hungarian–Yugoslav Non-Aggression Pact (December 12, 1940)
- Soviet–Yugoslav Non-Aggression Pact (April 6, 1941)
- Soviet–Japanese Neutrality Pact (April 13, 1941)
- German–Turkish Treaty of Friendship (June 18, 1941)
- Volker Krause, J. David Singer "Minor Powers, Alliances, And Armed Conflict: Some Preliminary Patterns", in "Small States and Alliances", 2001, pp 15-23, ISBN 978-3-7908-2492-6 (Print) ISBN 978-3-662-13000-1 (Online) 
- Brett Leeds, Jeffrey Ritter, Sara Mitchell, Andrew Long, "Alliance Treaty Obligations and Provisions, 1815-1944", "International Interactions: Empirical and Theoretical Research in International Relations", 2002, vol. 28, issue 3, p. 237-260, DOI: 10.1080/03050620213653 
- "No 10 rejects Nigel Farage election pact proposal". 2019-09-11. Retrieved 2019-09-11.
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