Matthias Corvinus, also called Matthias I, was King of Hungary and Croatia from 1458 to 1490. After conducting several military campaigns, he was elected King of Bohemia in 1469 and adopted the title Duke of Austria in 1487. He was the son of John Hunyadi, Regent of Hungary, who died in 1456. In 1457, Matthias was imprisoned along with his older brother, Ladislaus Hunyadi, on the orders of King Ladislaus the Posthumous. Ladislaus Hunyadi was executed, causing a rebellion that forced King Ladislaus to flee Hungary. After the King died unexpectedly, Matthias's uncle Michael Szilágyi persuaded the Estates to unanimously proclaim the 14-year-old Matthias as king on 24 January 1458. He began his rule under his uncle's guardianship, but he took effective control of government within two weeks.
As king, Matthias waged wars against the Czech mercenaries who dominated Upper Hungary and against Frederick III, Holy Roman Emperor, who claimed Hungary for himself. In this period, the Ottoman Empire conquered Serbia and Bosnia, terminating the zone of buffer states along the southern frontiers of the Kingdom of Hungary.