Siemowit II of Rawa

Siemowit II of Rawa (1283–1345), eldest son of Bolesław II of Płock, was a Piast duke who ruled central Masovia. He received Warsaw and Liw from his father in 1310, and after Bolesław died in 1313 made Rawa Mazowiecka his capital.

His long rule was spent maneuvering among Władysław I the Elbow-high, the Teutonic Order, Bohemia and Lithuania, repeatedly switching alliances to keep his duchy independent. He served as regent of Płock from 1336 to 1340 and welcomed the Peace of Kalisz between Poland and the Order in 1343.