The Battle of Slankamen was fought on 19 August 1691, near Slankamen in the OttomanSanjak of Syrmia (modern-day Vojvodina, Serbia), between the Ottoman Empire, and Habsburg Austrian forces during the Great Turkish War.
The battle saw a Turkish-Transylvanian force led by Emeric Thököly and Mustafa Köprülü suffer an overwhelming defeat by an Imperial army commanded by Ludwig Wilhelm of Baden. The Grand Vizir Mustafa Köprülü was killed by a stray bullet and the Ottoman army routed, leaving behind the war chest and their artillery. The battle was disastrous for the Turks and costly for the Austrians. The victory stabilized the Hungarian front and secured Hungary, Croatia and Transylvania for the Habsburgs.
The Ottomans suffered a series of defeats against the Archduchy of Austria in the 1680s, most notably at the Battle of Vienna in 1683, Buda in 1686, Belgrade in 1688 and Bosnia in 1689. However, with the beginning of the Nine Years War in the west, the early 1690s were to see an end to Habsburg conquests in the Balkans and a partial Ottoman recovery. Many German troops were withdrawn to fight King Louis‘ French forces on the Rhine, encouraging the Ottomans, led by the Grand VizierKöprülü Fazıl Mustafa Pasha, to counterattack.
In April 1690 the death of Michael I Apafi In April 1690 pushed the Sultan to nominate Hungarian Emeric Thököly prince of Transylvania, Thököly at the head of an army quickly occupied much of the principality. When the Imperial army left Belgrade to defeat Thököly in September, Köprülü managed to retake Belgrade and massacre the garrison which the Ottomans had lost in 1688.
In August 1691, Ludwig Wilhelm (Türkenlouis) marched down the Danube to provoke the Ottomans into another major battle, after gathering a new Imperial army of 33,000, including a 10,000 strong Serb militia, under the command of vice-voivoda Jovan Monasterlija.