Mazovia (Polish: Mazowsze). A Polish historical-geographic region in the Vistula Basin, of which the major city is Warsaw. Mazovia became part of Poland in the 10th century and a separate appanage in the mid-12th century. After the mid-13th century it was divided into a number of smaller principalities. By the mid-14th century it was a fiefdom of Poland, which finally absorbed it in 1526. In the east Mazovia bordered on Volodymyr principality and then the Principality of Galicia-Volhynia and maintained friendly relations with them. King Danylo Romanovych and his successors supported the Mazovian princes against Poland and acted to some extent as their protectors. The last prince of Galicia-Volhynia, Yurii II Boleslav, was the son of the Mazovian prince Trojden II and Mariia, the daughter of King Yurii Lvovych.
[This article originally appeared in the Encyclopedia of Ukraine, vol. 3 (1993).]