Louis II of Hungary
Upon succeeding his father, Suleiman the Magnificent began a series of military conquests in Europe. On August 29, 1526, he defeated Louis II of Hungary (1516–26) at the battle of Mohács. In its wake, Hungarian resistance collapsed and the Ottoman Empire became the preeminent power in South-Eastern Europe. In July 1683 Sultan Mehmet IV proclaimed a Jihad and the Turkish grand vizier, Kara Mustafa Pasha, laid siege to Vienna with an army of 138,000 men.