Ottokar I of Bohemia
He was the third son of the Polish high duke Henry II the Pious, by his wife Princess Anna, daughter of the Přemyslid king Ottokar I of Bohemia. After the heroic death of his father at the Battle of Legnica on 9 April 1241, Henry III was still a minor and found himself under the care of the mother together with his youngest brothers Konrad and Władysław.