The war greatly enhanced the prestige of Prussia, which won general recognition as a major European power, and of Frederick, who cemented his reputation as a preeminent military commander.

In 1750 Britain joined the anti-Prussian compact in return for guarantees of Austrian and Russian support in the case of a Prussian attack on the Electorate of Hanover, which George also ruled in personal union.

[3] At the same time, Maria Theresa, who had been disappointed with Britain's performance as her ally in the War of the Austrian Succession, followed the controversial advice of her Chancellor Wenzel Anton von Kaunitz by pursuing warmer relations with Austria's longstanding rival, the Kingdom of France.

King Louis XV responded to Prussia's realignment with Britain by accepting Maria Theresa's invitation to a new Franco-Austrian alliance, formalised with the First Treaty of Versailles in May 1756.

[6][7] Russia, likewise upset by the withdrawal of Britain's promised subsidies, drew closer to Austria and France, agreeing to a more openly offensive anti-Prussian coalition in April 1756.

Rather than wait for his enemies to move at a time of their choosing, he resolved instead to act preemptively, beginning with an attack against the neighbouring Electorate of Saxony, which he correctly believed was a secret party to the coalition against him.

[13] Strategic warfare in this period centred around control of key fortifications positioned so as to command the surrounding regions and roads, with lengthy sieges a common feature of armed conflict.

Occupied enemy territories were regularly taxed and extorted for funds, but large-scale atrocities against civilian populations were rare compared with conflicts in the previous century.

[27] In May 1757 the Second Treaty of Versailles strengthened the Franco-Austrian Alliance, with the French agreeing to contribute 129,000 soldiers to the fighting in Germany, along with subsidies of 12 million livres per year until Austria had recovered Silesia.

The resulting Battle of Kolín on 18 June ended in a decisive Austrian victory; the Prussian position was ruined, and the invaders were forced to lift the siege and withdraw from Bohemia altogether, pursued by Daun's army, which was enlarged by the Prague garrison.

The Imperials evaded the Prussians, however, and on 10 September Hanover and the British army of observation surrendered to France with the Convention of Klosterzeven, further exposing Prussia's western flank.

[52] Prussia had already exhausted its treasury in the 1757 campaign, and it now devalued its currency while imposing fresh taxes on occupied Saxony and on the Catholic Church in Silesia to raise funds for the new year.

[53] With the Saxon–Silesian front stabilised, Frederick ordered the bulk of his East Prussian forces under Lehwaldt to reinforce Pomerania, predicting that no new Russian advance would come until after the winter.

[40] Frederick abandoned the province to Russian occupation, judging it strategically expendable and preferring to concentrate on achieving another decisive victory in the Silesian theatre to force the Austrians to the peace table.

[59] Frederick decided that the time had come to invade Moravia and seize the fortified city of Olmütz, as he had planned the previous year, as soon as the last Austrians could be driven from Silesia.

On 30 June Austrian forces commanded by General Ernst von Laudon intercepted a massive supply convoy from Silesia bound for the Prussian army at Olmütz and destroyed it in the Battle of Domstadtl.

[63] Frustrated in Moravia, the Prussians fortified Saxony and Silesia, while Frederick led an army northward to repel the advancing Russians, who had by then reached the borders of Brandenburg, where they besieged and burned Küstrin.

[74] The Russians advanced westward toward the Oder, while Frederick led reinforcements northward to join Wedel and face Saltykov, leaving Prince Henry and General Heinrich August de la Motte Fouqué to see to the defence of Saxony and Silesia, respectively.

In early October a Russian corps under General Gottlob Heinrich Tottleben advanced through Neumark and joined Lacy's Austrians in briefly occupying Berlin, where they demanded ransoms, seized arsenals and freed prisoners of war.

However, the Russians soon pulled back to Frankfurt an der Oder for want of supplies,[78] while Lacy's force moved south to support Daun as he sought a decisive engagement with Frederick in Saxony.

[97] Daun, the chief Austrian commander, also ruled out major offensives for the year and made no plans to even attempt to reconquer Silesia, preferring to concentrate his efforts in Saxony against Prince Henry.

[98] Russian Marshal Alexander Buturlin, the new commander of Russia's forces in the theatre, coordinated with Laudon's Austrians to begin an advance in southern Silesia in April.

The allies ended the campaign with a modest victory by storming the fortress at Schweidnitz on 1 October, after which the Prussians fell back to winter quarters in northern Silesia and Brandenburg.

Austria was virtually bankrupt, and without French subsidies Maria Theresa could not afford a new invasion of Silesia; with France similarly exhausted, Louis was no longer willing to finance his ally's war.

[115] Austria was facing a severe financial crisis and had to reduce the size of its army, greatly decreasing its offensive power; without Russian troops or French subsidies, it had little hope of reconquering Silesia.

[113] Austria made a further concession by formally renouncing its claim to Silesia; in return, Prussia committed to support Maria Theresa's son, Archduke Joseph, in the forthcoming 1764 Imperial election.

Frederick the Great's personal reputation was enormously enhanced, as his debts to fortune (Russia's about-face after Elizabeth's death) and to British financial support were soon forgotten, while the memories of his energetic leadership and tactical successes were strenuously kept alive.

[120] Though sometimes depicted as a key moment in Prussia's rise to greatness, the war nonetheless left the kingdom's economy and population devastated, and much of the remainder of Frederick's reign was spent repairing the damage.

[129] By agreeing to vote for Archduke Joseph in the Imperial election, Frederick accepted the continuation of Habsburg pre-eminence in the Holy Roman Empire, though this was far less than Austria had hoped to win in the war.

[131] After the disappointment of the Third Silesian War Maria Theresa finally abandoned the hope of recovering Silesia, focusing instead on domestic reforms to better prepare the realm for future conflicts with Prussia.