Duke of Sieradz-Łęczyca
From 1138 to 1228, part of the Duchy of Kraków and Sandomierz, belonging to the high-dukes of Poland. == Dukes of Sieradz-Łęczyca == 1228–1232 Henry I the Bearded (Henryk I Brodaty) 1232–1233 Konrad of Masovia (Konrad Mazowiecki) 1234–1247 Konrad of Masovia (Konrad Mazowiecki) 1247–1260 Casimir I of Kuyavia (Kazimierz I Mazowiecki) 1260–1275 Leszek the Black (Leszek Czarny) 1275–1294 divided into two duchies of Sieradz and Lęczyca (see below) 1294–1297 Władysław I the Elbow-high (Władysław Łokietek) 1297–1305 Wenceslaus II of Bohemia (Wacław II Czeski) After 1305 parts of the united Kingdom of Poland initially as two vassal duchies, later incorporated as Łęczyca Voivodeship and Sieradz Voivodeship.