Duchy of Nysa
At the beginning of the 14th century, fourteen independent Duchies existed in Silesia: Brzeg, Wrocław, Świdnica, Jawor, Ziębice, Głogów, Ścinawa, Żagan and Oleśnica in Lower Silesia; Koźle, Cieszyn, Bytom, Niemodlin, Opole, Strzelce, Racibórz and Opava in Upper Silesia and the ecclesiastical Duchy of Nysa. Between 1327 and 1329 most dukes accepted the overlordship of Bohemian king John of Bohemia, who acquired the right of succession for all of these duchies. In the coming centuries all branches of the Silesian Piasts died out, and with the death of George William, Duke of Liegnitz the dynasty ceased to exist.