Danutė of Lithuania
Danutė of Lithuania (baptized Anna1358 – May 25, 1448) was a Lithuanian princess, daughter of Kęstutis, Grand Duke of Lithuania. She was married to Janusz I of Warsaw, one of the dukes of Masovia. Very little reliable information is known about her life.
The date of her marriage is confused in many sources. Jan Długosz in one instance claims that she got married in 1388 together with her cousin Alexandra of Lithuania, daughter of Algirdas. In another instance the historian claims that she was already married in 1382. Analysis of contemporary sources suggests that the marriage took place between 1371 and 1379. In 1379 Kęstutis in negotiations with the Teutonic Knights called Günter von Hohenstein, komtur of Ostróda, godfather of Danutė. It means that by that time she was already baptized and married. In 1371 Pope Gregory XI sent a letter to Siemowit III of Masovia, father of Janusz, urging him not to allow his subordinates to help pagan Lithuanians. If the marriage took place by that time, the pope would have certainly condemned the Christian duke for the alliance with the pagans.
In 1382, after escaping from Kreva, Vytautas the Great first asked his sister Danutė and his brother-in-law Janusz for help in the Lithuanian Civil War against his cousin Jogaila. However, he did not receive any assistance and had to turn to the Teutonic Knights. In 1440, after assassination of his father Sigismund Kęstutaitis, Michał Bolesław Zygmuntowicz might have also sought refuge in Danutė's lands. At the time Danutė was a widow, as Janusz died in 1429. It is believed that she died on May 25, 1448 leaving no heirs.
- (Lithuanian) Jonynas, Ignas (1937). "Danutė". In Vaclovas Biržiška. Lietuviškoji enciklopedija 5. Kaunas: Spaudos Fondas. pp. 1501–1502.