Vladimir Olgerdovich was a son of which ruler of medieval Lithuania?
Vladimir Olgerdovich Vladimir Olgerdovich (Belarusian: Уладзімер Альгердавіч , Lithuanian: "Vladimiras Algirdaitis" , Polish: "Włodzimierz Olgierdowic" , Ukrainian: Володимир Ольгердович ; died after 1398) was a son of Algirdas, Grand Duke of Lithuania, and his first wife Maria of Vitebsk. He was Grand Prince of Kiev from 1362 to 1394. His sons Ivan and Alexander started the Belsky and Olelkovich families.
Treaty of Vilnius (1559) The Treaty of Vilnius or Vilna was concluded on 31 August 1559, during the Livonian War, between the Livonian Order and the Polish-Lithuanian Commonwealth at Vilnius (Vilna, Wilna, Wilno). Gotthard von Kettler put the lands of the order under protection of Polish king and Grand Duke of Lithuania, Sigismund II Augustus. The alliance was intended to neutralize the imminent threat of annexation of the order's lands by Russia, yet despite earning military support from Polish-Lithuanian chancellor Mikołaj "the Black" Radziwiłł, Kettler was unable to prevent the occupation of most of Livonia by Russian forces. Thus, Kettler concluded a second treaty with Poland-Lithuania on 28 November 1561, transferring the remnants of the Teutonic Order State to the Polish Crown and the Grand Duchy of Lithuania, himself becoming a vassal of Sigismund II Augustus.