Опольское княжество
Originally a part of Lesser Poland, the area was acquired by the Silesian Piast Duke Władysław of Opole by a 1274 agreement with the Polish Princeps Bolesław V the Chaste. Zator then belonged to the Upper Silesian Duchy of Opole and after Władysław's death in 1281 fell to the Duchy of Cieszyn. It received town privileges in 1292.