Bolesław II's wife Sophia died in 1288. His second marriage was, like the first one, contracted for political reasons. The chose bride was Princess Kunigunde, sister of King Wenceslaus II of Bohemia; the wedding took place in the first half of 1291. Thanks to this union, the Bohemian King neutralized the claims of the Duke of Płock over the Seniorate, especially when he was able to conquer Kraków in 1291. Bolesław II also wanted to strengthen his position with Wenceslaus II, so he didn't hesitate when in 1292 he helped his brother-in-law in his war against Władysław I the Elbow-high.
The alliance between Masovia and Bohemia didn't lasted very long. In 1294 Konrad II died without male offspring, so Bolesław II became in the sole ruler over all Masovia. Feeling stronger, he broke relations with the Kingdom of Bohemia and reestablished relations with Władysław I the Elbow-high.
In 1295 Przemysł II became King of Poland. The following year, after his assassination, Bolesław II supported Władysław I in his brief war against Henry III of Głogów for the succession in Greater Poland.
The hostile policy towards the Kingdom of Bohemia forced Wenceslaus II to launched an attack against Masovia. Despite the siege and destruction of Płock, Bolesław II didn't change his political course, evidenced by his refusal to recognize Wenceslaus II as King of Poland in 1300 and the repudiation of his wife Kunigunde, who was sent back to Prague in 1302.
In the early 1300s Bolesław II founded the stronghold of Warsaw, contributing to its development in detriment of the nearby Czersk.
After 1305 Bolesław II wasn't present in any more political activity. The next information about him took place in 1310, when he granted two separate districts to his eldest two sons: Siemowit II received Warsaw and Trojden I received Czersk. In 1311, Borzysław becomes his Chancellor.[4]
Bolesław II died on 20 April 1313 in Wyszogród and, according to the reports of Jan Długosz, was buried at Płock Cathedral.[1]
Marriages and Issue
In 1279 Bolesław II married firstly to Gaudemantė (baptized as Sophia; d. 1288), a daughter of Grand Duke Traidenis of Lithuania. They had three children:
Siemowit II (1283 - 18 February 1345).
Trojden I (1284/86 - 13 March 1341).
A daughter [Ana?[5]] (ca. 1288 - aft. 1329), married after 13 August 1325 to Władysław of Legnica (div. before 13 Jan 1329).
In 1291 Bolesław II married secondly to Kunigunde (January 1265 - 27 November 1321), a daughter of Ottokar II and sister of Wenceslaus II, Kings of Bohemia; in 1302 she was repudiated and sent back to Prague, where she became a nun. They had two children:[6]
Euphrosyne (1292/94 – aft. 26 December 1327), married ca. 1304/09 to Władysław of Oświęcim.
Wenceslaus (1293/97 – 23 May 1336).