Wenceslaus of Płock

Wenceslaus (Wańko) of Płock (Polish: Wacław Płocki, Masovian dialect: Wańko Puocky; 1293/97 – 23 May 1336), was a Polish prince member of the House of Piast, Duke of Płock since 1313 and vassal of Bohemia from 1329.

He was the third son of Bolesław II of Płock but the only born from his second marriage with Kunigunde, daughter of King Ottakar II of Bohemia. He was probably named after his maternal uncle, King Wenceslaus II of Bohemia.

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. This division didn't satisfy anybody and lead to a brief war between the three brothers in 1316. Apart from a brief mention in the Roczniku miechowskim, the exact details of this conflict are unknown.

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.

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