After the death of their older brother, Vsevolod II, Sviatoslav and his brother Igor were driven out of Kiev by Iziaslav Mstislavich. Sviatoslav escaped, but Igor was captured and eventually killed in 1147. Sviatoslav fled to Chernigov but was ordered to relinquish his city, Novgorod-Seversk, to his cousins, Iziaslav Davidovich and Vladimir Davidovich. With the assistance of his ally, Yuri Dolgoruki, and his father-in-law, Aepa Khan, Sviatoslav began a war against his cousins, but was forced to flee to Karachev. There on January 16, 1147, Sviatoslav defeated the Davidovichi brothers.
Upon his death in 1164, his wife briefly ruled as princess regnant of Chernigov.[2]
Family
In 1108, Sviatoslav married a Cuman princess, daughter of Aepa son of Girgen, with whom he had a daughter and a son, Oleg II Svyatoslavich. In 1136 Svyatoslav married a second time, to a woman of Novgorod, who bore his famous son, Igor Sviatoslavich.
Dimnik, Martin. The Dynasty of Chernigov, 1146-1246, 2000
Raffensperger, Christian; Birnbaum, David J. (2021). "N. N. Iaropolkovna. b. 1074 – d. 1158". Rusian genealogy at genealogy.obdurodon.org. Retrieved 21 July 2024.