Géza II was King of Hungary and Croatia from 1141 to 1162. He was the oldest son of Béla the Blind and his wife, Helena of Serbia. When his father died, Géza was still a child and he started ruling under the guardianship of his mother and her brother, Beloš. A pretender to the throne, Boris Kalamanos, who had already claimed Hungary during Béla the Blind's reign, temporarily captured Pressburg with the assistance of German mercenaries in early 1146. In retaliation, Géza, who came of age in the same year, invaded Austria and routed Henry Jasomirgott, Margrave of Austria, in the Battle of the Fischa.