Suleiman's march to Vienna was also an attempt to assist his vassal, John Szapolyai who claimed the throne of Hungary.

His campaign was marked by speedy success, on September 8 Buda surrendered to the Ottomans and John Szapolyai was installed as King of Hungary.

Suleiman then went further taking Esztergom, Tata, Komárom and Győr[1] so that much of Ferdinand I's gains the previous two years were lost.

The arrival of the Sultan's massive host in Central Europe caused much panic across Europe - Martin Luther, who had believed that the Ottomans were God's punishment against the sins of Christians[3] modified his views and wrote the book the War with the Turks in 1529 urging that "the scourge of God" should be fought with great vigour.

However, when Suleiman began besieging Vienna it would prove to be his first and most decisive blunder.