After the Ottoman Sultan Mehmed II decided to invade Hungary, Ladislaus and Ulrich II left the kingdom. The sultan laid siege to Belgrade. Hunyadi relieved the fortress on 22 July 1456, but he died two weeks later. Ladislaus and Ulrich II returned to Hungary and tried to force Hunyadi's son, also named Ladislaus, to renounce all royal castles and revenues, but Ladislaus Hunyadi murdered Ulrich II on 9 November, forcing Ladislaus to grant an amnesty to him. However, most Hungarian barons were hostile towards Ladislaus Hunyadi. With their support, Ladislaus captured him and his brother, Matthias. After Ladislaus Hunyadi was executed in March 1457, his relatives stirred up a rebellion against Ladislaus, forcing him to flee from Hungary. Ladislaus died unexpectedly in Prague. He was the last male member of the Albertinian Line of the House of Habsburg.