List of Famous people named Siemowit

Siemowit IV, also known as Siemowit IV the Younger, was a Polish prince member of the House of Piast from the Masovian branch, from 1373/74 Duke of Rawa, and after the division of the paternal inheritance between him and his brother in 1381, ruler over Rawa, Płock, Sochaczew, Gostynin, Płońsk and Wizna, since 1386 hereditary Polish vassal, since 1388 ruler over Belz, during 1382–1401 he lost Wizna and during 1384–1399 and 1407–1411 he lost Zawkrze, during 1384–1399 he lost Płońsk, taken by the Teutonic Order.

Siemowit III of Masovia was a prince of Masovia and a co-regent of the lands of Warsaw, Czersk, Rawa, Gostynin and other parts of Masovia.

Siemowit V of Rawa, was a Polish prince member of the House of Piast from the Masovian branch. He was a Duke of Rawa Mazowiecka, Płock, Sochaczew, Gostynin, Płońsk, Wizna and Belz during 1426-1434 jointly with his brothers, and after the division of the paternal inheritance between him and his brothers in 1434, sole ruler over Rawa Mazowiecka, Gostynin and Sochaczew.

Siemowit of Dobrzyń, was a Polish prince member of the House of Piast, Duke of Brześć Kujawski during 1267–1288, Duke of Dobrzyń during 1288–1293, 1295–1303 and 1305–1312, during 1293–1295 in captivity in Lithuania, during 1303–1305 deposed, since 1306 hereditary vassal of the Kingdom of Poland.

Siemowit of Cieszyn was a Polish prince, member of the Piast dynasty in the Cieszyn branch.

Siemowit I of Masovia, was a Polish prince member of the House of Piast, Duke of Czersk during 1247-1248, Duke of Masovia during 1248-1262, ruler over Sieradz during 1259-1260.

Siemowit II of Rawa, was a Polish prince member of the House of Piast, Duke of Warsaw and Liw during 1310-1313, after a new division with his brothers since 1313 ruler over Rawa Mazowiecka, Sochaczew, Zakroczym, Gostynin, Ciechanów and Wizna, regent of Płock during 1336–1340.

Siemowit of Bytom (Polish: Siemowit bytomski;, was a Duke of Bytom during 1312–1316 and Duke of Gliwice from 1340 until his death.

Siemowit VI of Płock, was a Polish prince member of the House of Piast from the Masovian branch. He was a Duke of Płock, Rawa Mazowiecka, Belz, Płońsk, Zawkrze and Wizna during 1455-1461/62 jointly with his brother, since 1459 ruler over Gostynin.