Ladislaus the Posthumous

Albert II died in 1439 and left everything to his unborn son; when the boy arrived on 22 February 1440, only Austria accepted the inheritance. His mother seized Hungary's crown and had him crowned in May, but the Diet called it invalid and elected a Polish king instead, triggering civil war. Frederick III, King of the Romans, took over as guardian and kept Ladislaus at court in Wiener Neustadt for years while regents ran his kingdoms. After his Polish rival died at Varna in 1444, Hungary offered to recognize him if Frederick released him; Frederick refused, so the Hungarians made John Hunyadi regent in 1446. The Estates of Austria finally forced Ladislaus' release in 1452, but real power stayed with Hunyadi in Hungary and George of Poděbrady in Bohemia. After Hunyadi died defending Belgrade against Mehmed II in 1456, Ladislaus returned to Hungary and tried to strip Hunyadi's sons of their castles; the son murdered Ladislaus' chief advisor Ulrich II on 9 November, then fell into the king's hands and was executed in March 1457. Rebellion erupted, Ladislaus fled to Prague, and died there on 23 November 1457 - the last male of his line.