As Duke Frederick II of Austria had been killed at the 1246 Battle of the Leitha River, the ducal line of the Babenberg dynasty had become extinct. Margrave Herman VI of Baden, through his marriage with Gertrude, had raised inheritance claims to the Austrian and Styrian possessions. However, after the death of Emperor Frederick II in 1250, no strong Imperial authority existed to assert his title. Though he was backed by Pope Innocent IV and anti-king William of Holland, Herman could not prevail against the claims raised by the mighty Přemyslid king Wenceslaus I of Bohemia and his warlike son Ottokar II.