From the 8th to the 10th centuries, the area was dominated by the Khazars, a Turkic people who had earlier migrated from the east onto the Pontic-Caspian Steppe, where they reputedly converted to Judaism. After the defeat of the Khazar Khanate in 965 Kievan prince Svyatoslav conquered the area, it came under the rule of Kievan Rus', and it then formed the Tmutarakan principality. Later, due to the increasing claims of Byzantium at the end of the 11th century, the Tmutarakan principality came under the authority of the Byzantine emperors (until 1204).