Amongst the nomadic Ugrians and agricultural Slays of the north their frontier fluctuated widely, and in its zenith Khazaria extended from the Dnieper to Bolgari upon the middle Volga, and along the eastern shore of the Caspian to Astarabad.
Khazaria became the apanage of his eldest son, and the centre of government amongst the eastern subjects of the Hun (448).
Throughout the 6th century Khazaria was the mere highway for the wild hordes to whom the Huns had opened the passage into Europe, and the Khazars took refuge (like the Venetians from Attila) amongst the seventy mouths of the Volga.
The allies were defeated, and the Moslems undertook the subjugation of Khazaria (651).
The khakan and his chieftains were captured and compelled to embrace Islam (737), and till the decay of the Mahommedan empire Khazaria with all the other countries of the Caucasus paid an annual tribute of children and of corn (737861).