KHAZARS (known also as Chozars, Akatziroi, Khazirs, Khwalisses, and Ugri Bielii), an ancient people who occupied a prominent place amongst the secondary powers of the Byzantine state-system. They were the organizers of the transit between the Black Sea and the Caspian, the universal carriers between East and West. The area under their control varied greatly, but the normal Khazaria may be taken as the area between the Caucasus, the Volga, and the Don, with the outlying province of the Crimea (Little Khazaria).
Sarogours (i.e., White Ogors, possibly the Barsileens of the Volga delta) were swept along in a flood of mixed Tartar peoples which the conquests of the Avars had set in motion. The Khazars and their companions broke through the Persian defences of the Cau casus. They appropriated the territory up to the Kur and the Aras and roamed at large through Iberia, Georgia and Armenia. The Persian king implored the emperor, Leo I., to help him defend Asia Minor at the Caucasus (457), but Rome was herself too hard pressed, nor was it for so years that the Khazars were driven back and the Pass of Derbent fortified against them (c. 5o7).
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 7o mouths of the Volga. The pressure of the Turks in Asia precipitated the Avars upon the West. The conquering Turks followed in their footsteps (56o-8o). They beat down all opposition, wrested even Bosporus in the Crimea from the empire, and by the annihilation of the Ephthalites completed the ruin of the White Race of the plains from the Oxus to the Don. The empires of Turks and Avars, however, ran swiftly their barbaric course, and the Khazars arose out of the chaos to more than their ancient renown. They issued from the land of Barsilia, and extended their rule over the Bulgarian hordes left masterless by the Turks, compelling the more stubborn to migrate to the Danube (641). The agricultural Slays of the Dnieper and the Oka were reduced to tribute, and before the end of the 7th century the Khazars had annexed the Crimea, had won complete command of the Sea of Azov, and, seizing upon the narrow neck which sep arates the Volga from the Don, had organized the portage which has continued since an important link in the traffic between Asia and Europe. The alliance with Byzantium was revived. Simul taneously, and no doubt in concert, with the Byzantine cam paign against Persia (589), the Khazars had reappeared in Armenia, though it was not till 625 that they appear as Khazars in the Byzantine annals. They are then described as "Turks from the East," a powerful nation which held the coasts of the Cas pian and the Euxine, and took tribute of the Viatitsh, the Severians, and the Polyane. The khakan, enticed by the prom ise of an imperial princess, furnished Heraclius with 40,000 men for his Persian war, who shared in the victory over Chosroes.