The Third Silesian War was a theatre of the Seven Years' War. The name is used to describe Prussia's war against Austria and its allies between 1756 and 1763, fought mainly in Silesia, Bohemia and Upper Saxony. The war was the third and last in a series of Silesian Wars fought between Frederick the Great's Prussia and Maria Theresa's Austria; like the earlier two, it ended with Prussia in control of the region of Silesia.
The war's cost in blood and treasure was high on both sides, and it ended inconclusively when neither of the main belligerents could sustain the conflict any longer. The 1763 Treaty of Hubertusburg, which ended the war, resulted in no territorial changes, but Austria agreed to recognize Prussia's sovereignty in Silesia in return for Prussia's support for the election of Maria Theresa's son, Archduke Joseph, as Holy Roman Emperor. The war greatly enhanced the prestige of Prussia, which won general recognition as a major European power, and of King Frederick, who cemented his reputation as a military genius.:166–167
While the Seven Years' War was a global conflict among many belligerents, its Central European theatre turned on lingering grudges from the War of the Austrian Succession (1741–1748). The Treaty of Aix-la-Chapelle, which concluded the earlier war, confirmed Prussian King Frederick II's seizure of the region of Silesia from the Habsburg Monarchy through two previous Silesian Wars. The defeated Archduchess Maria Theresa of Austria nevertheless fully intended to retake the lost province and reassert Austria's hegemony in the Holy Roman Empire; after peace was restored, she set about rebuilding her armed forces and seeking out new alliances.
Together with Tsaritsa Elizabeth of Russia, Maria Theresa formed a defensive agreement known as the Treaty of Two Empresses in 1746 which aligned Austria and Russia against Prussia; a secret clause guaranteed Russia's support for Austria's claims in Silesia. Elizabeth feared that Prussia's growing power would obstruct the path of Russia's westward expansion and saw Frederick's kingdom as a rival for influence in the Commonwealth of Poland–Lithuania. In 1750, Great Britain joined the anti-Prussian compact (despite dynastic links, the British viewed Prussia as an ally and proxy of the French) in return, the British expected Austrian and Russian defense in the case of a Prussian attack on the Electorate of Hanover, which King George II also ruled in personal union. At the same time, though, Maria Theresa, who had been disappointed with Britain's performance as her ally in the War of the Austrian Succession, took the controversial step of pursuing warmer relations with Austria's longstanding rival, the Kingdom of France.:197–198
Britain elevated tensions in 1755 by offering to finance Russian military deployments in return for a Russian army standing ready to attack Prussia's eastern frontier. Alarmed by this encirclement, Frederick began working to separate Britain from the coalition. On 16 January 1756, Prussia and Britain agreed to the Convention of Westminster, under which Prussia now undertook to guarantee Hanover against French attack, in return for Britain's withdrawal of its offer of military subsidies to Russia. This move created a new Anglo-Prussian alliance and incensed the French court, which responded to Prussia's realignment with Britain by accepting Maria Theresa's invitation to a new Franco-Austrian alliance, formalized with the First Treaty of Versailles in May 1756, and to be consolidated by a dynastic alliance with marriage of the Dauphin to one of Maria Theresa's daughters. This series of political maneuvers came to be known as the Diplomatic Revolution.
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. As Austria and Russia made open preparations for renewed war, Frederick became convinced that Prussia would be attacked in the spring of 1757; rather than wait for his enemies to move at a time of their choosing, he resolved instead to preemptively invade the neighboring Electorate of Saxony, which he believed (incorrectly) was a secret party to the coalition against him. Prussian troops crossed the Saxon frontier on 29 August 1756, beginning the Third Silesian War.:198–199
King Frederick's broad strategy had three parts. First, he meant to seize Saxony and eliminate it as a threat to Prussia, then use the Saxon army and treasury to bolster the Prussian war effort. Second, he would advance from Saxony into Bohemia, where he might set up winter quarters at Austria's expense. Third, he would invade Moravia from Silesia, seize the fortress at Olmütz, and advance on Vienna to force an end to the war. To begin, Frederick divided his army in three: he placed a small force under Field Marshal Hans von Lehwaldt in East Prussia to guard against any Russian invasion from the east; he stationed Field Marshal Count Kurt von Schwerin in Silesia with 25,000 soldiers to deter incursions from Moravia and Hungary; finally, he personally led the main Prussian army into Saxony.:427
This aggressive attack on neutral Saxony, however, galvanized the Austrian coalition, and in particular increased France's commitment to offensive war against Prussia. The Holy Roman Empire declared war on Prussia on 17 January 1757, contributing a 40,000-man Imperial Army (Reichsarmee) under Austrian leadership. The May 1757 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. In return, Austria promised (after the victory was won) to grant France control of the Austrian Netherlands, a long-coveted prize for the French. Russia also committed 80,000 men to the conflict, hoping to seize East Prussia and then exchange that territory with Poland for control of Courland. Sweden also agreed to invade Prussian Farther Pomerania, looking to recovering the territories lost to Prussia after the Great Northern War. In all, then, the Austrian coalition sought a total partition of the Kingdom of Prussia.:199–200
The Prussian army marched in three columns: on the right were about 15,000 men under the command of Prince Ferdinand of Brunswick; on the left were 18,000 men under the command of the Duke of Brunswick-Bevern; in the centre was Frederick himself, with Field Marshal James Keith commanding a corps of 30,000 troops. Prince Ferdinand was to advance on the town of Chemnitz, while the Duke of Brunswick-Bevern was to traverse Lusatia to seize Bautzen. Meanwhile, Frederick and Keith would attack the Saxon capital at Dresden.:427
The Saxon and Austrian armies were unprepared for Frederick's preemptive strike, and their forces were scattered; Prussians occupied Dresden with little or no resistance from the Saxons.:428 At the Battle of Lobositz on 1 October, Frederick prevented the isolated Saxon army from being reinforced by an Austrian army under General Browne.:430–438 The Prussians then fully occupied Saxony; after the Siege of Pirna ended later in October, the Saxon army surrendered and was forcibly incorporated into the Prussian army. Britain had been surprised by the sudden Prussian offensive but now began shipping supplies and subsidies to its new ally.:465
After wintering in Saxony, on 18 April 1757 the main Prussian army advanced in multiple columns through the Ore Mountains into Bohemia, seeking to decisively defeat the Austrian forces.:37 On 21 April the column led by the Duke of Brunswick-Bevern encountered an Austrian corps led by Count Königsegg near Reichenberg; the ensuing Battle of Reichenberg ended in a solid Prussian victory, and the Prussian force continued to advance toward Prague.
The invading columns reunited north of Prague, while the retreating Austrians formed up to the city's east, and on 6 May the two armies fought the Battle of Prague. Both sides suffered heavy casualties, but the Prussians forced the Austrians back into the fortified city, which the invaders then besieged. Learning of the attack on Prague, Austrian commander Leopold von Daun advanced from the east with a force of 30,000 men.:39 Daun arrived too late to join the battle of Prague, but he collected some 16,000 Austrians who had escaped from the battle along the way; with these reinforcements he slowly moved to relieve the city.
Trying to simultaneously besiege Prague and face Daun, Frederick was forced to divide his armies. He sent 5,000 troops from the siege to reinforce a 19,000-man army under the Duke of Brunswick-Bevern at nearby Kolín.:454 Without sufficient force to resist Daun's advance, the Prussians decided to attack the Austrian positions. The resulting Battle of Kolín on 18 June ended in a decisive Austrian victory; the Prussian position was ruined, and Frederick was forced to lift the siege and withdraw from Bohemia altogether, pursued by Daun's army (enlarged by the Prague garrison). The failure to take Bohemia meant the ruin of Frederick's strategy, leaving no realistic prospect of a march on Vienna.
Prussia's reversal in Bohemia paralleled the entry of new belligerents on the Austrian side. In the summer of 1757, a Russian force of 75,000 troops under Field Marshal Stepan Fyodorovich Apraksin invaded East Prussia and took the fortress at Memel.:460 Advancing further, the Russians engaged and defeated a smaller Prussian force led by Marshal Lehwaldt in the Battle of Gross-Jägersdorf on 30 August. However, the victorious Russians were unable to take Königsberg, having expended their supplies at Memel and Gross-Jägersdorf, and retreated soon afterward; recurring difficulties with logistics limited the offensive capabilities of the large Russian army and allowed East Prussia to hold out longer than might have been expected.:22 Sweden, too, declared war on Prussia in September, invading Prussian Pomerania on 13 September with 17,000 men and beginning the Pomeranian War.:460 The need to defend core territories on other fronts reduced Prussia's offensive capacity in Bohemia and Silesia.:176
In the autumn Austrian forces began a counter-advance into Prussian-controlled Saxony and Silesia, while a combined French and Reichsarmee force under the Prince of Soubise approached the theatre from the west.:41 On 7 September, Austrians under Charles of Lorraine advancing into Upper Lusatia defeated a Prussian force at the Battle of Moys, killing Prussian commander Hans Karl von Winterfeldt.:302 Prince Charles's army then advanced westward, hoping to link up with Soubise's force after the latter had traversed Saxony.:41
Between 10 and 17 October, Count András Hadik, a Hungarian general serving in the Austrian army, unexpectedly maneuvered his modest hussar force of 5,000 around the Prussians and advanced to Berlin, occupying part of the capital for one night. The city was spared for a ransom of 200,000 thalers.:467 When King Frederick learned of this humiliating occupation, he immediately sent a larger force to free the city; Hadik and his hussars, however, abandoned the city and safely returned to the Austrian lines. Hadik was later promoted to the rank of marshal in the Austrian Army, having executed what may be the most famous hussar action in history.:22
After this series of imperial advances, on 5 November a Prussian corps under Frederick engaged Soubise's much larger force near the village of Rossbach in Saxony. The ensuing Battle of Rossbach ended in a stunning Prussian victory, in which Frederick lost fewer than 1,000 men, while the Franco-German force under Soubise lost around 10,000.:469–472 This victory secured Prussia's control of Saxony for the time, and its effect on the morale of both sides was dramatic. After the embarrassing defeat at Rossbach, French interest in the Silesian War declined sharply; with the signing of Third Treaty of Versailles in March 1758, France greatly reduced its financial and military contributions to the Austrian coalition,:254–255 leaving Rossbach as the only battle between the French and Prussians during the entire war.:41
In November, the combined Austrian armies of Prince Charles and Count Daun reached Breslau, where they were opposed by the Silesian garrison under the Duke of Brunswick-Bevern. The Austrians had overwhelming numbers, and in the 22 November Battle of Breslau they drove the Prussians from the field. Bevern himself was taken prisoner, and the bulk of his remaining forces retreated toward Glogau, leaving behind some thousands to garrison the city against a siege; the commander of the garrison surrendered Breslau to the Austrians on 25 November in return for safe passage.:573
When Frederick learned of the fall of Breslau, his 22,000 men marched 274 kilometres (170 mi) in twelve days to regroup with the retreating Prussian troops from Breslau at Liegnitz. The augmented army of about 33,000 men arrived near Leuthen, 27 kilometres (17 mi) west of Breslau, to find 66,000 Austrians in possession of the city. Despite his troops' fatigue from the rapid march, Frederick engaged the superior Austrian force on 5 December and won another unexpected victory in the Battle of Leuthen.:476–481 The Prussians pursued Prince Charles's defeated army all the way back to Bohemia, while the Austrian and French forces still within Breslau were besieged until their surrender on 19–20 December, bringing all of Silesia back under Prussian control.:161–167
After this major defeat, Charles of Lorraine was removed from his command and replaced by Daun, who was now promoted to Field Marshal. Frederick hoped the major victories at Rossbach and Leuthen would bring Maria Theresa to the peace table,:166 but she was determined not to negotiate until she had retaken Silesia.:575–576 With the Saxon–Silesian front stabilized, Frederick ordered the bulk of his East Prussian forces under Marshal Lehwaldt to reinforce Pomerania, predicting that no new Russian advance would come until the spring. The enlarged Prussian army quickly drove the Swedes back, occupied most of Swedish Pomerania, and blockaded its capital at Stralsund through the winter.:473 Over the winter, Duke Ferdinand of Brunswick, now commander of Hanover's army, launched a series of offensives that drove the French out of northern Germany and across the Rhine, securing Prussia's western flank for the duration of the war.:486
In January 1758 a Russian army again invaded East Prussia, where the few remaining Prussian troops put up little resistance.:41 Frederick abandoned the province to Russian occupation, judging it strategically expendable, and instead concentrated on provoking a decisive battle in the Silesian theatre to force the Austrians out of the war. On 11 April 1758, the British formalised their alliance with Prussia in the Anglo-Prussian Convention, in which they committed to provide Prussia with a subsidy of ₤670,000 annually (equivalent to ₤91.5 million in 2017) and to make no separate peace. Britain also dispatched 9,000 troops to reinforce the Duke of Brunswick's Prussian–Hanoverian army in the Rhineland.:179–182
In May 1758 Frederick's army invaded Moravia from Silesia and laid siege to the fortified city of Olmütz.:489 Austrian Marshal Daun chose to avoid direct engagements with the Prussian force, focusing instead on harassing its supply lines. By late June the city's defenses were badly damaged, but the Prussian army's supplies were likewise low. On 30 June one of Daun's generals intercepted a massive supply convoy bound for the besieging Prussian army at Olmütz and destroyed it in the Battle of Domstadtl. After this loss, the Prussians broke off the siege and withdrew from Moravia, abandoning their final major invasion of Austrian territory of the war.:148–155
Frustrated in Moravia, Frederick turned north to repel the advancing Russian army that had by then reached the borders of Brandenburg, recalling the Prussian troops that had besieged Stralsund through the winter to bolster his forces. On 25 August a Prussian army of 35,000 men under Frederick engaged a Russian army of 43,000 commanded by Count William Fermor just east of the Oder in Neumark at the Battle of Zorndorf.:494–499 Both sides fought to exhaustion and suffered heavy casualties, but the Russians withdrew, and Frederick claimed victory.:162–169 The withdrawal of Prussian soldiers from Swedish Pomerania led to a renewed Swedish offensive in September which progressed as far as Neuruppin; but, after failing to unite with either Russian or Austrian forces, the Swedes pulled back to Swedish Pomerania for the winter.:500
Meanwhile, in the autumn Marshal Daun's Austrians again began probing into Saxony, and on 14 October they surprised the main Prussian army near Hochkirch in Lusatia, achieving a solid victory at the Battle of Hochkirch.:501–506 The Prussians abandoned much of their artillery, and Field Marshal Keith was killed in battle, but the survivors retreated in good order, and Daun declined to pursue them. The Austrians ultimately made little progress in Saxony, despite their victory at Hochkirch, and were thwarted in an attempt to retake Dresden. Eventually, Daun's troops were forced to withdraw into Bohemia for the winter, leaving Saxony under Prussian occupation, where Frederick hurried to rebuild his decimated army.:195–202
In April 1759 Frederick led his main army from Saxony into Lower Silesia to keep the Russian army in western Poland–Lithuania separated from Daun's Austrians in Bohemia. Meanwhile, a smaller Prussian force under Prince Henry remained in Saxony to harass Bohemia through the Ore Mountains, winning the Battle of Peterswalde and a series of other minor engagements, as well as destroying several Austrian ammunition dumps and bridges before retreating into Saxony. The Russians continued to press into Neumark; on 23 July the Russian Count Saltykov led 47,000 men in defeating 26,000 Prussians commanded by General Carl Heinrich von Wedel at the Battle of Kay. However, poor coordination and mistrust between the Russians and Austrians prevented Saltykov and Daun's forces from uniting after the victory. Still, the Russians advanced westward, and on 3 August they reached and occupied Frankfurt an der Oder, where they received some Austrian reinforcements under General Ernst von Laudon.:232–233
Determined to drive back the Russians, Frederick combined his army with survivors from the Battle of Kay, and on 12 August he attacked the Russian position around the village of Kunersdorf, east of Frankfurt. The resulting Battle of Kunersdorf was a crushing Russo-Austrian victory, totally scattering the Prussian army and opening the way to Berlin for the invading coalition— yet the allies again did not pursue the defeated Prussians or occupy Berlin.:250 Heavy Russian casualties at Kunersdorf and disagreement between the Russian and Austrian leadership led the cautious Count Saltykov to hold back his forces, giving the Prussians time to regroup.:74
The Russian army's tenuous supply lines also made it difficult for them to press home the victory deep in enemy territory; Russian logistics were so poor that, in October 1759, the Austrians agreed to supply the Russians out of their own quartermaster's department. However, the demands of both the Austrian and Russian armies proved beyond Austria's capacity, and, in practice, the Russians received little in the way of supplies from the Austrians.:22 During the retreat from Kunersdorf Frederick had thought the war lost, but his enemies' internal conflicts and hesitant leadership gave Prussia a second chance, a mistake that Frederick later termed the "Miracle of the House of Brandenburg.":419–420
Meanwhile, in September Austrian forces in Bohemia pressed into Saxony (which Frederick had largely emptied of defenders in preparation for Kunersdorf), quickly occupying Dresden and most of the electorate. A Prussian relief force under Prince Henry marched south to contest Saxony again, where they retook Leipzig and sharply defeated a larger Austrian force at the 21 September Battle of Korbitz. In response, Daun sent a relief force of his own into Saxony, only to have it destroyed by Prince Henry's Prussians at the 25 September Battle of Hoyerswerda. Chagrined at the prospect of losing Saxony again, Daun then moved his own main force westward into Saxony, leaving behind the Russians, who withdrew into Poland for the winter.:74 While the Prussian army struggled to rebuild itself in Brandenburg during the autumn, Daun forced the surrender of an entire Prussian corps sent to harass lines of communication between Saxony and Bohemia on 21 November in the Battle of Maxen. Another Austrian victory in Saxony at the 4 December Battle of Meissen ended the campaigning year.
In the spring of 1760, Austrians under Laudon advanced in Lower Silesia, besieging the fortress at Glatz on 7 June. Prussian general Fouqué led a force to relieve the fortress, but Laudon engaged and destroyed them at the 23 June Battle of Landeshut; Glatz eventually fell on 26 July. Frederick led his main force into Saxony, briefly besieging Dresden in mid-July, but withdrew to maneuver against Daun's forces in Lower Silesia;:279–283 he finally engaged Laudon's corps near Liegnitz on 15 August. The resulting Battle of Liegnitz was a solid Prussian victory, as Frederick defeated Laudon's army before Daun's larger force could arrive to support him, disrupting the Austrians' maneuvers and preserving Prussian control of Lower Silesia.
With most of Prussia's forces in Silesia, the Russians under Count Saltykov and Austrians under General Lacy briefly occupied Berlin in early October, where they demanded ransoms, seized arsenals and freed prisoners of war. However, Saltykov's men soon pulled back to Frankfurt for want of supplies,:74 while Lacy's forces withdrew to support Daun as he sought a decisive engagement with Frederick in Saxony.:194:293 The main Prussian and Austrian armies finally faced each other on 3 November near Torgau, where the succeeding Battle of Torgau proved very costly for both sides; in the end the Prussians controlled the field and claimed victory, but both armies were badly weakened and soon retreated to winter quarters.:196
Prussia's pyrrhic victory at Torgau resulted in few strategic gains, since Daun still controlled Dresden, and Laudon's army still had the run of Silesia.:196 On the other hand, the Austrians, who had hoped to decide the war once and for all at Torgau, were bitterly disappointed to have suffered still another defeat by a smaller Prussian force, and Maria Theresa's deteriorating finances were beginning to constrain the war effort. The battle left the war-making capacity of both sides so depleted that neither had any realistic prospect of bringing the Silesian War to a decisive close without outside help.:196
In the spring of 1761 Prussia could muster only 100,000 troops, many of them raw recruits, and its situation was desperate.:491 However, the Austrian and Russian forces were also heavily depleted, and neither side had the men or supplies to launch a major offensive. The Russian army slowly advanced through Brandenburg, still struggling to supply its men by wagon train from magazines in Poland. Deprived of men, the Prussian defenders resorted to harassing convoys to delay the enemy advance, executing a number of successful raids. Meanwhile, Laudon's Austrians gradually occupied more of Silesia, storming the fortress at Schweidnitz on 1 October.
Beginning on 22 August, Russian forces under Zakhar Chernyshyov and Pyotr Rumyantsev besieged and blockaded the Prussian Pomeranian port of Kolberg; the town was strongly defended and held out well, but several attempts to break the siege were repulsed. Then, in October Frederick ordered much of the garrison to withdraw to Berlin and defend Brandenburg; the town finally capitulated on 16 December. The fall of Kolberg cost Prussia its last port on the Baltic Sea,:492 and it gave Russia a way to supply its armies in Central Europe by sea, rather than overland through Poland. The resulting benefits to Russian logistics threatened to tip the balance of power decisively against Prussia the following year.:75
As 1762 began, the Prussian armies had dwindled to only 60,000 men, and it was doubtful whether they could prevent a renewed Russian and Austrian advance to Berlin. A total Prussian collapse seemed imminent; the British now threatened to withdraw their subsidies if Prussia did not offer concessions to secure peace, a threat that was made good later that year by the new British prime minister, Lord Bute. Then, on 5 January 1762 the ailing Russian Empress Elizabeth died; her nephew and successor, Tsar Peter III, was an ardent admirer of Frederick's, and he at once reversed Elizabeth's foreign policy and ordered a ceasefire with Prussia.:204–205
Peter negotiated an armistice with Frederick in March and lifted the Russian occupation of East Prussia and Pomerania, and on 5 May the two powers concluded the Treaty of Saint Petersburg, ending their war with Prussia's pre-war borders confirmed in the north and east. Peter went on to mediate the 22 May Treaty of Hamburg, ending the war between Prussia and Sweden, with all of Prussia's territory preserved; after signing a new alliance with Prussia on 19 June, he even placed a corps of 18,000 Russian troops under Frederick's command. A second "Miracle of the House of Brandenburg" had occurred.:457–459
With its northern and eastern flanks now completely secure and Russian reinforcements enlarging its army, Prussia concentrated all of its remaining strength against Austria. On 9 July, Tsar Peter was deposed and replaced by his wife, Tsarina Catherine II (later to be known as Catherine the Great); Catherine immediately withdrew from the alliance her husband had formed with Prussia, but neither did she rejoin the war on the Austrian side.:204–205 In the summer, Frederick led his main force back into Silesia and engaged Daun's army on 21 July near Burkersdorf; the Prussian victory in the Battle of Burkersdorf led to the recovery of most of Silesia from Austrian control. In the autumn, Prince Henry led a secondary army into Saxony, where he met with the Austrian defenders of Dresden near Freiberg; the 29 October Battle of Freiberg saw the defenders shattered and pursued back to Dresden, after which Prussian forces occupied the majority of Saxony. In November the principal belligerents agreed to an armistice in Saxony and Silesia, while Prince Henry's army pursued some Reichsarmee forces into Franconia and raided pro-Austrian principalities in the Empire.
By the beginning of 1763, Prussia had recovered nearly all of Silesia from the Austrians, and after the Battle of Burkersdorf it controlled most of Saxony outside of Dresden; Austria still held Dresden and the southeastern edge of Saxony, along with the County of Glatz to the south of Silesia. The warring powers in Central Europe had essentially fought to a stalemate. Prussia's finances were stable, but the country was devastated, and the realm's manpower was spent; an offensive against Dresden seemed impossible. Austria, for its part, was facing a severe financial crisis and had to reduce the size of its army, greatly decreasing its offensive power; without Russian support it had little hope of reconquering Silesia. The belligerents in the wider Seven Years' War had already begun peace talks; now, negotiators from Austria, Prussia and Saxony convened on 30 December 1762 at Hubertusburg palace, near the front lines in Saxony, to discuss terms of peace.
Frederick had earlier considered offering East Prussia to Russia in return for Peter's support for his seizure of Saxony, but Catherine's withdrawal meant that Russia was no longer a belligerent and did not participate in the negotiations. The warring parties eventually agreed to restore their respective conquests to each other: Austria would withdraw from Glatz, restoring full Prussian control of Silesia, in exchange for Prussia's evacuation of Saxony, which would be returned to Elector Augustus (who would receive no other reparations from Prussia). With these swaps, the borders in the region arrived precisely back at status quo ante bellum. Austria made a further concession by formally renouncing its claim to Silesia; in return, Prussia committed to support the election of Maria Theresa's son, Archduke Joseph, as Holy Roman Emperor. With that, the belligerents agreed an end to the Silesian War in the Treaty of Hubertusburg, signed 15 February 1763.
The return to territorial status quo ante meant that none of the belligerents in the Silesian War gained the prizes they had aimed at: Prussia was unable to keep any part of Saxony, while Austria failed to recover its lost province of Silesia. Nonetheless, the outcome of the war has generally been considered a diplomatic victory for Prussia, which not only retained Silesia, but also compelled Austria to acknowledge its sovereignty in the province, forestalling any further Silesian Wars. More fundamentally, Prussia showed itself to be credible rival to Austria by successfully surviving intact what could have become a war of partition.:199–200
Prussia emerged from the war as a great power whose continental importance could no longer be disputed, and the leading power of Protestant Germany.:215–219 Frederick the Great’s personal reputation was enormously enhanced, as his debts to fortune (Russia’s volte-face after Elizabeth’s death) and to British financial support were soon forgotten, while the memories of his energetic leadership and tactical genius were strenuously kept alive.:90 His small kingdom had held its own while being simultaneously invaded by Austria, Russia, Sweden, and (for a time) France, an accomplishment that appeared miraculous to contemporary observers.:200 After 1763, armies around the world sent their officers to Prussia to learn the secrets of the realm's outsize military power, making Prussia one of the most imitated states in Europe.:90
Though sometimes depicted as a key moment in Prussia's rise to greatness, the war nonetheless left Prussia weak: the kingdom's economy and population were devastated (though Frederick's extensive agrarian reforms and encouragement of immigration soon eased both problems); its armed forces had suffered heavy losses (particularly in the officer corps), and the state could not afford to rebuild the army to what it had been before the war.:210–213 In the succeeding War of the Bavarian Succession (1778–1779), the Prussians fought poorly, despite again being personally led by Frederick, and the Prussian army did not fare well against revolutionary France in 1792–1795. In 1806 the Prussians were annihilated by Napoleon's French at the Battle of Jena; only after a series of reforms motivated by the disasters of 1806–1807 did Prussian power again begin to grow.:313
Austria was not able to retake Silesia or realize any other territorial gains. However, it did preserve Saxony from Prussian control, slowing the growth of its new northern rival. Its military performed far more respectably than during the War of the Austrian Succession, which seemed to vindicate Maria Theresa's administrative and military reforms since that war. Thus, the war in great part restored Austria's prestige and preserved its position as a major player in the European system. Also, by promising to vote for Archduke Joseph in the Imperial election, Frederick accepted the continuation of Habsburg preeminence in the Holy Roman Empire. Prussia's confirmation as a first-rate power and the enhanced prestige of its king and army, however, were long-term threats to Austria's hegemony in Germany.:216
Indeed, the Empire now held several ambitious middle powers eager to gain at Austria's expense. Elector Augustus of Saxony was also King of Poland–Lithuania and could call on the resources of that realm to advance his interests in Germany. The Electorate of Hanover had gained tremendously through its personal union with Great Britain and could now draw on British power in German conflicts. Bavaria's strength was also waxing, as it asserted military and foreign policies ever more independent from those of the Empire. The Silesian Wars made clear that the Habsburg Monarchy would need continued reform if it was to retain its dominant position in European power politics.:212