- First Silesian War, 1740–42
- Second Silesian War, 1744–45
- Third Silesian War, 1756–63
The first two can be viewed in the context of the larger War of the Austrian Succession, while the "Third Silesian War" is better known as the Seven Years' War. Silesia was strategically important to Prussia because "it significantly blunted the capacity of Prussia's two chief foes—Austria and Russia—to meddle in Prussian affairs". Prussian victory (and possession of Silesia) foreshadowed a wider struggle for control over the German-speaking peoples that would culminate in the Austro-Prussian War of 1866.
First Silesian War
The First Silesian War inaugurated, and is generally seen in the context of, the wider ranging War of the Austrian Succession. It owed its origins to the Pragmatic Sanction of 19 April 1713 whereby the Habsburg emperor Charles VI decreed the imperial succession arrangements as set out in his will, according precedence to his own daughters over the daughters of his (by now deceased) elder brother Joseph I. This proved prescient: in May 1717 the emperor’s own eldest daughter was born and on his death in 1740, she duly succeeded as Archduchess of Austria as well as to the thrones of the Bohemian and Hungarian lands within the Habsburg Monarchy as Queen Maria Theresa.
During the emperor’s lifetime the Pragmatic Sanction was generally acknowledged by the imperial states but when he died it was promptly contested both by the Hohenzollern scion Frederick II, who had just ascended the Prussian throne, and by the Wittelsbach elector Charles Albert of Bavaria. While Charles launched a claim to the imperial throne and the Habsburg territories, King Frederick II aimed at the annexation of Silesia, a Bohemian crown land since 1335.
Frederick based his demands on a 1537 inheritance treaty of the Silesian duke Frederick II of Legnica with the Hohenzollern elector Joachim II of Brandenburg, whereby the Silesian duchies of Legnica, Wołów and Brzeg were to pass to the Electorate of Brandenburg on the extinction of the Silesian Piasts. The Bohemian king Ferdinand of Habsburg, aware of the Hohenzollern ambitions, had immediately rejected the agreement; nevertheless in 1675 the "Great Elector" Frederick William of Brandenburg raised claim to the principalities, when with the death of Duke George William of Legnica the Piast line finally had died out. At that time no attempt had been made to implement these old treaty provisions, and when in the course of the 1685 Edict of Potsdam the Elector entered into an alliance with the Habsburg emperor Leopold I, he was persuaded to renounce his claims in return for the assignment of the Silesian Świebodzin (Schwiebus) exclave and a payment. However, after the accession of Frederick William's son and successor Elector Frederick III of Brandenburg, the emperor in 1695 enforced the restitution of Świebodzin, which allegedly only had been personally assigned to late Frederick William for life. Furious Frederick III in turn again insisted on the centuries-old Brandenburg claims to the Silesian Piast heritage.
Forty-five years on, an extensive alliance formed in support of Prussia’s newly asserted claims on Silesia. King Frederick II was supported by the electorates of Bavaria, Saxony and Cologne, as well as by the kingdoms of France, Spain, Sweden and Naples along with various smaller European powers. The shared objective within the alliance was the destruction or at least the diminution of the Habsburg Monarchy and of its dominant influence over the other German states. The Habsburgs found themselves supported by the Russian Empire along with the maritime powers, the Dutch and the British (in personal union with the Electorate of Hanover), whose imperial aspirations beyond Europe always inclined them to join available eighteenth-century European wars on the anti-French side. Britain and Austria were bound by the Anglo-Austrian Alliance which had existed since 1731.
On 8 November 1740, King Frederick II ordered the mobilization of the Prussian Army. According to his plan of attack, two corps would defeat a small Austrian infantry regiment and occupy the whole Silesian lands. On December 11 he issued an ultimatum to Austria demanding the surrender of Silesia. In turn, he promised to acknowledge the Pragmatic Sanction and to give his vote as Brandenburg prince-elector in the Imperial election to Maria Theresa's husband Duke Francis of Lorraine. Instead of awaiting the Austrian response, he marched against Silesia with an army of about 27,000 men five days later, hailed by the Protestant population.
After a two-month campaign, Prussian forces had occupied all of Silesia, with only small Austrian garrisons entrenched in the fortresses of Głogów, Brzeg, and Nysa. Having abandoned winter quarters in 1741, the Prussian forces started their spring campaign: on March 9 Prince Leopold II of Anhalt-Dessau took Głogów by storm. The remaining Austrian troops gathered near Brzeg under the command of Wilhelm Reinhard von Neipperg, where they were defeated by the Prussians under Frederick's Generalfeldmarschall Kurt Christoph Graf von Schwerin in the Battle of Mollwitz on April 10. The Silesian capital Wrocław (Breslau) was occupied by August 10, a first armistice was concluded on October 9.
After his Saxon, Bavarian and French allies had stormed Prague in November, Frederick, to safeguard his interests, again mobilized his troops and likewise campaigned Bohemia and Moravia, occupying Olomouc on December 26. The Prussian victory in the Battle of Chotusitz on May 17, 1742, ended the First Silesian War. By the preliminary Peace of Breslau, confirmed by the Treaty of Berlin on July 28, 1742, the bulk of Silesia and the Bohemian County of Kladsko were ceded to Prussia and was later consolidated as the Province of Silesia. Only the southern portion of Upper Silesia (with the duchies of Cieszyn, Krnov and Opava) remained under Habsburg control, later called Austrian Silesia.
Second Silesian War
The Second Silesian War took place from 1744 to 1745. The Austrians had lost Silesia to Prussia in the Battle of Mollwitz. This was the time when the Austrians, under the command of Field Marshal Otto Ferdinand von Abensberg und Traun, attempted to gain control of Silesia once again. The Prussians were again led by King Frederick the Great.
The Battle of Hohenfriedberg on June 4, 1745, was fought through a "series of separate actions," with each part of the Prussian army fighting its own uncoordinated battle. Because the Saxons and Austrians were unable to support each other during the battle, they "allowed the Prussians time to recover from their own tactical lapses and win a victory that was significant enough to give the battle's name to one of Germany's greatest marches." After the Prussian victory, Frederick did not pursue the opposing armies.
In the Battle of Soor on September 29, 1745, Frederick's Prussians faced an Austrian army led by Prince Charles Alexander of Lorraine with 39,000 men. Frederick tried to obtain Graner-Koppe from Prince Charles where the Prussians met with cannon fire. The Prussians won after a closely fought battle consisting of a series of attacks and regimental fighting.
Whilst Frederick was sure the war was over, Empress Maria Theresa had not given up her claims to Silesia. "She became even more determined to put Prussia in its proper place by force of arms." Seeking peace with France and Russia, she hoped to beat Prussia and gain control of Silesia once again. Frederick was informed of her movements to regain control and “responded with a pre-emptive strike” against her Saxon allies. This was the Battle of Kesselsdorf which was won by the Prussian general Leopold I, Prince of Anhalt-Dessau; the Saxons were led by Frederick Augustus Rutowsky.
The signing of the Treaty of Dresden on December 25, 1745, ended the Second Silesian War between Austria, Saxony, and Prussia. Maria Theresa recognized Frederick the Great's sovereignty over Silesia and the Duchy of Glatz in return for "Frederick's agreement to support the election of her consort Francis Stephen as Holy Roman Emperor."
Third Silesian War
As part of the pan-European Seven Years' War, Austria once more tried to get back Silesia, while Prussia attempted to grab Saxony. The collapse of the Anglo-Austrian Alliance in 1756 meant that Britain had now changed sides, and in this war they supported Prussia against the Austrians.
After battles in 1761–62 went well for Russian and Austrian forces, in January 1762, Austria was suddenly abandoned by their ally with the ascension of Peter III of Russia who recalled his army from within Berlin and Pomerania upon the death of Empress Elizabeth of Russia (d. 5 January 1762 [O.S. 25 December 1761]).
While Peter was assassinated himself the next summer, before Catherine the Great succeeded him and could once again bring Russia into an alliance, peace talks that were already in progress about the wider war concluded in February 1763 — and, worse for Austria, Peter had mediated an agreement between Prussia and Sweden, allowing Frederick II's forces to consolidate his position and bolster Prussia's claims in January and February. Consequently, Prussia was then confirmed with her Silesian possessions in the Treaty of Hubertusburg.
- Browning, Reed (2005). "New Views on the Silesian Wars". Journal of Military History 69 (2): 521–534. doi:10.1353/jmh.2005.0077.;
- Showalter, Dennis E. (1995). The Wars of Frederick the Great. Longman. pp. 84–88. ISBN 978-0582062603.
- Millar, Simon (2001). Kolin 1757: Frederick the Great's First Defeat. Osprey Publishing. p. 9. ISBN 9781841762975.
- Citino, Robert (2005). The German Way of War. Lawrence: University Press of Kansas. ISBN 0700614109.
- Craig, Gordon (1955). The Politics of the Prussian Army. New York: Oxford University Press.
- Duffy, Christopher (1996). The Army of Frederick the Great (2nd ed.). Chicago: Emperor's Press. ISBN 188347602X.