born in 1350 in the castle of present-day old trakai (senieji trakai), vytautas was the son of kęstutis and his wife birutė. vytautas was a cousin and childhood friend of jogaila (władysław ii jagiełło), who became king of poland in 1386. around 1370, he married anna, who gave birth to sophia of lithuania. sophia was married to vasily i, grand prince of moscow, and mother and regent to their son vasili ii. after anna's death in 1418, vytautas married her niece juliana olshanska, daughter of ivan olshanski who outlived him. because of the relationship between the two women, the bishop of vilnius was unwilling to perform the ceremony without a papal dispensation; however, jan kropidło did not have such scruples and married them on 13 november 1418.according to the 16th century bychowiec chronicle, his first wife was maria łukomska, however, this is not confirmed by other sources.