sentences:  Siewierz in Upper Silesia was ruled by the Silesian Piasts as part of the Duchy of Bytom under Duke Casimir.In 1312 he granted the town to his youngest son Mieszko, who renounced it in favour of his brother Władysław.In 1337 it was acquired by Casimir I, Duke of Cieszyn, whose scion Wenceslaus I sold it to the Archbishop of Kraków in 1443.