Mstyslav Volodymyrovych (baptismal name – Constantine; 983–1036, Chernihiv) – Prince of Tmutorokan (988 – ?) and Chernihiv (1026–1036).
Son of the Grand Prince of Kyiv Volodymyr Sviatoslavych the Great, and, probably, Adele. According to the administrative reform of 988 got from his father the Tmutorokan land, where he defended frontiers and conducted successful external policy in the Ciscaucasia, for instance he defeated the Circassian Khan Rededia (for which he was called the Brave in the The Lay of Ihor’s Host). In 1016 fought against the Khazars, and in 1022 conquered finally the Circassians.
In 1023, with the help of the Khazars and the Circassians seized the Chernihiv-Siversk land. He defeated the troops of his brother Yaroslav the Wise in the battle near Lystvyn in 1024. After this victory Mstyslav suggested a peace agreement in Horodets (1026), according to which he became a prince of Chernihiv lands. In 1031, along with Yaroslav and troops of the German Emperor, waged a campaign against Poland, to help him to regain the Cherven towns, occupied by the Poles in 1015–1019. Until 1036 he and his brother governed Kyivan Rus as the duumvirate, and Mstyslav chose Chernihiv as his residence. Built a church in Tmutorokan, founded the Transfiguration Cathedral in Chernihiv (has survived to the present day), where he was buried.