Skirgaila

Skirgaila (Latin: Schirgalo;Belarusian: Скіргайла; Polish: Skirgiełło, also known as Ivan/Iwan; ca. 1353 or 1354 – 11 January 1397 in Kiev; baptized 1383/1384 as Casimir) was a regent of the Grand Duchy of Lithuania for his brother Jogaila from 1386 to 1392. He was the son of Algirdas, Grand Duke of Lithuania, and his second wife Uliana of Tver.

After Algirdas' death in 1377, Jogaila became the Grand Duke. It is believed that dynastic disputes that soon erupted between him and his uncle Kęstutis and his cousin Vytautas the Great were largely inspired by Skirgaila. It is known about his travels to the Teutonic Knights in 1379 just a year prior to the controversial Treaty of Dovydiškės. Skirgaila was the chief supporter of his brother Jogaila and helped him to imprison both Kęstutis and Vytautas in Kreva castle during the Lithuanian Civil War (1381–1384). Some historians speculate that Kęstutis' death after a week in prison was in fact assassination carried out by Skirgaila. As a reward for a job well done, Skirgaila received the Duchy of Trakai.

When Jogaila was preparing for the Union of Kreva, Skirgaila was actively involved in the negotiations and even headed a diplomatic mission to Poland. The negotiations succeeded and Jogaila married Jadwiga of Poland and was crowned as King of Poland in 1386. He left Skirgaila as his regent in Lithuania. However, Skirgaila was not popular with the nobles and Vytautas saw this as an opportunity to gain power. In 1389 he started a new civil war, but after an unsuccessful attack on Vilnius he had to seek help from the Teutonic Knights. In 1392 Jogaila and Vytautas signed the Ostrów Agreement, and Vytautas became his regent of the Grand Duchy of Lithuania. The Duchy of Trakai was returned to Vytautas as his patrimony.

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