11-12 September – On this day

The Battle of Vienna took place in Vienna on the 11th/12th in 1683, after the imperial city of Vienna had been besieged by the Ottoman Empire for two months.

The battle was fought by the Holy Roman Empire of the German Nations in league with the Polish-Lithuanian Commonwealth (Holy League) against the invading Muslim Ottoman Empire and chiefdoms of the Ottoman Empire, and took place at Kahlenberg Mountain near Vienna. The battle marked the first time Poland and the Holy Roman Empire had cooperated militarily against the Turks, and it is often seen as a turning point in history, after which “the Ottoman Turks ceased to be a menace to the Christian world”. In the ensuing war that lasted until 1698, the Turks lost almost all of Hungary to the Holy Roman Emperor Leopold I.

The Ottomans Besiege Vienna
The Ottomans Besiege Vienna

The battle was won by the combined forces of the Holy Roman Empire of the German Nations and the Polish–Lithuanian Commonwealth, the latter represented only by the forces of the Crown of the Kingdom of Poland. (The march of the Lithuanian army was delayed, and they reached Vienna after it had been relieved.) The Viennese garrison was led by Ernst Rüdiger Graf von Starhemberg, an Austrian subject of Holy Roman Emperor Leopold I. The overall command was held by the senior leader, the King of Poland, John III Sobieski, who led the Polish forces.

The opposing military forces were those of Ottoman Empire and those of Ottoman fiefdoms commanded by Grand Vizier Merzifonlu Kara Mustafa Pasha. An Ottoman army of 90,000 plus men began the siege on 14 July 1683. The Turkish forces consisted of elite Janissaries (12,000 men paper-strength) with supporting forces of c.70,000 + men. The decisive battle took place after the united relief army of about 46,000 men had arrived.

Historians suggest the battle marked the turning-point in the Ottoman–Habsburg wars, a 300-year struggle between the Holy Roman and Ottoman Empires. In fact, during the sixteen years following the battle, the Austrian Habsburgs gradually recovered and dominated southern Hungary and Transylvania, which had been largely cleared of Turkish forces. The battle is also noted for including the largest known cavalry charge in history.