Summer in Vienna is hot and humid. As July, 1683 began, Hapsburg Archduke Leopold I, Holy Roman Emperor, had retreated to his estate at Perchtoldsdorf to escape the oppressive heat of the city. There, Leopold received disturbing news: the war with the Ottoman Empire had taken an alarming turn. The Austrian Hapsburg army of 30,000 men was in full retreat, unable to halt an Ottoman invasion force numbering 140,000 to 300,000 troops. By July 7, when Leopold returned to Vienna, the Turks were within a few miles of the city. Leopold and the residents of Vienna were forced to flee.
Vienna is situated on the banks of the Danube River where east-west overland trade routes converge. For hundreds of years, trade brought prosperity and gave the city its strategic importance. Culturally, Vienna was hardly a backwater, but the rich artistic and intellectual community the city would become famous for still lay in the future. For its day, it was fairly large, with a population f about 100,000. By the time the Ottoman siege began, only about 15,000 people remained, including 11,000 Hapsburg troops charged with Vienna’s defense. Though no one at the time could know it, the stage was set for a battle that would decide the balance of power in Europe between the western Christian culture and the Islamic east.
EVENTS LEADING UP TO THE WAR
The Ottoman Empire had expanded into the Balkans centuries before and briefly reached as far as Vienna in 1529. For the most part, however, the limits of Ottoman rule extended no further than parts of Hungary. That changed in the 1670s. Partly, this was due to Turkish expansionism, but much of the cause was Leopold’s policies in Hungary. That country was home to ethnic Magyars who resented Hapsburg rule, and a large population of Protestants. Europe was at the end of a century and a half of religious strife, and Leopold, as Holy Roman Emperor, was not inclined to be tolerant of Protestantism. During the 1670s, he pursued a policy of repression against both ethnic unrest and Protestantism.
For Kara Mustafa Pasha, Grand Vizier of the Ottoman Sultanate, this presented an opportunity. Mustafa provided support to Hungarian rebels led by Imre Thokoly. By 1681, Thokoly had seized control of much of the region bordering Austria, and the Ottoman Empire promptly recognized him as the “King of Upper Hungary.” However, Hapsburg forces continued to attack. Mustafa persuaded the Sultan to mobilize Turkish forces, and war was declared in August, 1682.
The timing was the first of several strategic blunders on Mustafa’s part. By waiting until August, he made it impossible to attack Vienna before winter, effectively precluding a campaign until the following spring, giving Austria almost a year’s warning. Leopold set about forging alliances with other countries and updating Vienna’s defenses. The most important step was to sign a mutual defense treaty with King John Sobieski of Poland.
THE SIEGE OF VIENNA
Ottoman forces reached Vienna on July 14, after finally beginning the campaign on April 1, 1683. Mustafa sent a demand for surrender. These were only 11,000 defenders. Yet those remaining in the city refused. This may have been as much Mustafa’s own doing as bravery on the part of the defenders. Word had reached them of the fate of the villagers of Perchtoldsdorf. After surrendering to the advancing Turks, the villagers had been slaughtered.
General Ernst Starhemberg was in charge of Vienna’s defense. He had buildings outside the city walls razed, creating a clear field of fire attackers would have to cross. Mustafa decided to lay siege, rather than attack directly. Mustafa may have had no choice. The Ottoman army was deeply divided. Large contingents of Rumanians and Moravians were there under duress and might have refused to carry out a frontal assault.
To speed the campaign, the Turks began to dig trenches to provide cover and tunnels to reach under the city alls. Gunpowder detonated in these tunnels would demolish the fortifications. In response, the troops under Starhemberg also dug tunnels to intersect those of the attackers so these could be sealed off. By September 12, Starhemberg’s force of 11,000 dwindled to 4,000. The rest were dead or wounded, and food was all but exhausted. To make matters worse, the Turks had succeeded in tunneling to the city walls.
THE BATTLE OF VIENNA, SEPTEMBER 12, 1683
At 4 AM on the morning of September 12, the defenders saw bonfires on Kahlen Berg, a hill outside Vienna. John Sobieski, ruler of the Polish-Lithuanian Commonwealth, had arrived with the Holy League army of some 80,000 troops. At dawn, Polish infantry led the first assault against the Turks. At this point, Mustafa made his final mistake. Believing he was on the verge of entering the city, he continued to attack Vienna while defending his rear from the Holy League forces. He almost proved correct. Workers had set a great charge of gunpowder in the tunnel under the city wall and lit the fuse. But Starhemberg’s men broke through and defused the charge just in time.
By mid-afternoon, the Ottoman forces were exhausted from fighting attackers on two sides. Sobieski gathered the cavalry and personally led 20,000 horsemen in the largest cavalry charge in history, dealing a crushing blow to the Turks. By nightfall, the Ottoman forces were in full retreat.
LEGACY OF THE BATTLE OF VIENNA
For Mustafa, the defeat was ultimately fatal. He was executed by strangulation on orders from the Sultan. Thokoly ended his days in obscurity, an unwelcome exile among the Turks. The battle of Vienna proved to be more than a simple defeat for the Sultanate. Hapsburg forces began to press forward in a long war that ended only in 1699 with the expulsion f the Turks from Hungary and most of their other holdings in Europe. The threat of Ottoman hegemony in Europe was finished. The fledgling Austro-Hungarian Empire went on to become one of Europe’s great powers for more than two centuries.