Wenceslaus of Płock

Unlike his older half-brothers Siemowit II and Trojden I, Wenceslaus didn't receive his own district until the death of their father in 1313, when he inherited Płock.

Early in his reign, Wenceslaus tried to pursue a neutral policy with his two powerful neighbors, the Teutonic Order and Poland; a clear manifestation of this was his refusal to testifying during the Teutonic-Polish trial in Inowrocław or the agreement that he signed on 14 April 1321 in the city of Golub with the Teutonic Knights (represented by Frederick von Wildenberg), by which the Masovian rulers committed to refuse passage to the Lithuanians troops who fight against help the Order.

Despite the treaty with the Teutonic Order, initially Wenceslaus managed to maintain good relations with Lithuania, evidenced when in 1323 he allowed Lithuanian troops to cross his territory to invaded the district of Dobrzyń.

In this fight, Wenceslaus strongly supported the Teutonic Order; in revenge, Wladysław I besieged and burned Płock; after Gostynin managed to resist the attack of the Polish forces, Wenceslaus asked the help of the Teutonic Order, and thanks to this, the Masovian rulers are able to rejected the army of Wladysław I from their domains.

After this betrayal, an army led by King John of Bohemia and with the help of Teutonic Knights, invaded Płock, forcing Wenceslaus to surrender.