khagan

…of semireligious character called a khagan—who wielded little real power—and by tribal chieftains, each known as a beg. The state’s military organization also seems to have lacked the forcefulness of those of the greater Turkic-Mongol empires. The Khazars seem to have been more inclined to a sedentary way of life,…

… (called, like the Khazar emperor, khagan) is mentioned by Islamic and Western sources. This Volga Rus khagan state may be considered the first direct political antecedent of the Kievan state.