REFN: 6001AN Svyatoslav I, Grand Prince of Kiev Born circa 942 Acceded in 945 Died in 972 , ambushed and killed. Svyatoslav was only about three years old when his fath er Igor was murdered in 945, hence his mother St. Olga acted as Regent of Kie v until 964. Olga's first official act was to wreak vengeance on the Drevlane s who had murdered her husband by besieging and burning their town of Koros ten. In 957 Olga went with a large retinue to Constantinople, accepted Christ ianity, and received baptism. In 964, Svyatoslav took over the government, alt hough his mother continued to administer home affairs until her death in 970. Svyatoslav led Kievan Rus's military conquest of the Bulgars, responding t o attacks by the Khazar tribe. He in turn was ambushed and killed by Byzanti nes from Pecheneg in the south, who, according to legend, converted Svyatos lav's skull into a drinking vessel. Svyatoslav married Malousha and they had a son: