Duchy of Łęczyca (Polish: Księstwo łęczyckie) was one of the duchies of Poland. It was created around 1231 from Province of Łęczyca, a part of the Seniorate...

Polish–Lithuanian Commonwealth. The Prince-Bishopric of Warmia (Polish: Biskupie Księstwo Warmińskie,) was a semi independent ecclesiastical state, ruled by the...

(województwo pomorskie, Gdańsk) Duchy of Warmia (Księstwo Warmińskie, Lidzbark Warmiński) Duchy of Prussia (Księstwo Pruskie, Królewiec) Płock Voivodeship (województwo...