Adalbert the Victorious (died May 26, 1055 in Melk) was Margrave of Austria from 1018 until his death. He extended the eastern border of the then small Ostmark of Bavaria as far as the rivers Morava/March and Leitha and supported King Henry III in his battles against Hungary and Bohemia. He resided in the Lower Austrian Babenberg castle of Melk, where Stift Melk was to develop later.