Mstislav Vladimirovich (; ; ) was the earliest attested prince of Tmutarakan and Chernigov in Kievan Rus'. He was a younger son of Vladimir the Great, Grand Prince of Kiev. His father appointed him to rule Tmutarakan, an important fortress by the Strait of Kerch, in or after 988. He invaded the core territories of Kievan Rus', which were ruled by his brother, Yaroslav the Wise, in 1024. Although Mstislav could not take Kiev, he forced the East Slavic tribes dwelling to the east of the Dniester River to accept his suzerainty. Yaroslav the Wise also accepted the division of Kievan Rus' along the river after Mstislav had defeated him in a battle fought at Listven by Chernigov (presents-day Chernihiv, Ukraine). Mstislav transferred his seat to the latter town, and became the first ruler of the principality emerging around it. Early years Mstislav was one of the many sons of Vladimir the Great, Grand Prince of Kiev. His exact position in Vladimir's family is disputed, because Vladimir, who had seven wives and many concubines before his conversion, fathered two sons called Mstislav, according to the Primary Chronicle. One of them was born to Rogneda of Polotsk, who had been forced to be the first wife of Vladimir in the late 970s. The second Mstislav was born to a Czech woman. Historians debate whether the future prince of Tmutarakan and Chernihiv was the son of Rogneda or Vladimir's Czech wife: the first option is preferred by George Vernadsky, the second by Janet Martin. Prince of Tmutarakan Vladimir the Great administered large portions of Kievan Rus' through his sons by placing them in towns in the borderlands. The Primary Chronicle narrates, under the year 988, that Mstislav became the prince of Tmutarakan after the death of one of his brothers, Vysheslav of Novgorod. Vernadsky writes that Mstislav, as ruler of Tmutarakan, assumed the title of khagan. Tmutarakan was an important town controlling the Strait of Kerch between the Sea of Azov and the Black Sea. It was separated from other parts of the Kievan Rus' by the steppes. Under Mstislav, who was the first known prince of Tmutarakan, the town developed into an important emporium for traders from the Kievan Rus' and the Byzantine Empire. Vladimir the Great died in 1014 while preparing a campaign against his rebellious son, Izyaslav. Mstislav remained neutral during the civil war which followed his father's death