Battle of Vienna

The Battle of Vienna was fought on 12 September 1683 on the slopes of the Kahlenberg and the plain outside Vienna, ending a two-month Ottoman siege of the Habsburg capital. A relief army of imperial, German and Polish troops under King John III Sobieski of Poland routed the Ottoman army of Grand Vizier Kara Mustafa Pasha. The victory began a long war in which the Habsburgs drove the Ottomans out of most of Hungary.

More than 150 years after Suleiman the Magnificent's failed siege of 1529, Hungary was still divided between the Habsburgs and the Ottoman Empire. In the Habsburg-ruled part, the emperor Leopold I's pressure on Protestants and on noble privileges provoked a revolt led by Imre Thököly, which the Ottomans supported. The ambitious grand vizier Kara Mustafa persuaded Sultan Mehmed IV to launch a great campaign, prepared for more than a year. Leopold in turn concluded an alliance with Poland in March 1683, by which each would help the other if its capital was threatened.

The Ottoman army, which according to its own campaign records numbered about 170,000 at the outset including auxiliaries and support troops, though modern estimates of its fighting strength are far lower, advanced through Hungary in early summer. Leopold and his court left the city. The siege began on 14 July. The garrison, roughly 11,000 to 16,000 soldiers with several thousand civilian volunteers, was commanded by Count Ernst Rüdiger von Starhemberg. The Ottomans brought relatively little heavy artillery and relied on mines dug under the walls, while trenches crept towards the fortifications. Through August and early September the defenders, short of food and weakened by dysentery, fought off assault after assault, and by early September the walls had been breached in places.

Sobieski left Kraków in mid-August. His Polish army joined imperial troops under Duke Charles of Lorraine and contingents from Saxony, Bavaria and other German states north-west of Vienna, crossing the Danube at Tulln. The combined force numbered roughly 70,000 to 80,000 men, and as the senior ruler present, Sobieski took overall command. Louis XIV of France, the Habsburgs' rival, stayed out of the coalition. On 11 September the allies reached the Kahlenberg heights above the city.

Fighting began early on 12 September as the Ottomans attacked the allies while they were still deploying. Kara Mustafa, still hoping to take the city, kept many of his best troops in the siege trenches. Through the day the imperial and German infantry pushed down the wooded slopes on the left, and in the afternoon the Poles advanced on the right. Late in the afternoon Sobieski launched a massive cavalry charge, led by the Polish winged hussars and often described as one of the largest cavalry charges in history. The Ottoman line broke, Kara Mustafa fled, and the great camp, with its tents, supplies and treasure, was taken.

Casualty figures vary. The Ottomans lost perhaps 15,000 to 20,000 men in the battle, including prisoners, and many more during the siege, while the relief army lost a few thousand. The Vienna garrison had suffered heavily during the siege, and the surrounding countryside was ravaged, with many thousands of civilians carried off into slavery. Kara Mustafa was executed on the sultan's orders in Belgrade on 25 December 1683.

The victory led to the Holy League of 1684, uniting the emperor, Poland, Venice and later Russia against the Ottomans. Habsburg armies took Buda in 1686 and won further victories, notably under Prince Eugene of Savoy at Zenta in 1697. By the Treaty of Karlowitz in 1699 the Ottomans ceded most of Hungary and Transylvania to the Habsburg Monarchy. Vienna was never again besieged by the Ottomans, and the battle became a lasting symbol in Austria and Poland.

Our 1650 map shows central Hungary still under Ottoman rule, and our 1700 map shows it as Habsburg territory after the war that followed the battle, with the Polish-Lithuanian Commonwealth to the north.