Decades later, Leo III (ruled 717–741) made a similar alliance to co-ordinate strategy against a common enemy, the Muslim Arabs. He sent an embassy to the Khazar qağan Bihar and married his son, the future Constantine V (ruled 741–775), to Bihar's daughter, a princess referred to as Tzitzak, in 732. On converting to Christianity, she took the name Irene. Constantine and Irene had a son, the future Leo IV (775–780), who thereafter bore the sobriquet, "the Khazar". Leo died in mysterious circumstances after his Athenian wife bore him a son, Constantine VI, who on his majority co-ruled with his mother, the dowager. He proved unpopular, and his death ended the dynastic link of the Khazars to the Byzantine throne. By the 8th century, Khazars dominated the Crimea (650–c. 950), and even extended their influence into the Byzantine peninsula of Cherson until it was wrested back in the 10th century. Khazar and Farghânian (Φάργανοι) mercenaries constituted part of the imperial Byzantine Hetaireia bodyguard after its formation in 840, a position that could openly be purchased by a payment of seven pounds of gold.
Decades later, Leo III (ruled 717–741) made a similar alliance to co-ordinate strategy against a common enemy, the Muslim Arabs. He sent an embassy to the Khazar qağan Bihar. and married his son, the future Constantine V (ruled 741–775), to Bihar's daughter, a princess referred to as !Tzitzak, in 732. On converting to Christianity, she took the name Irene. Constantine and Irene had a son, the future Leo IV (775–780), who thereafter bore the sobriquet, "the Khazar". Leo died in mysterious circumstances after his Athenian wife bore him a son, Constantine VI, who on his majority co-ruled with his mother, the dowager. He proved unpopular, and his death ended the dynastic link of the Khazars to the Byzantine throne. By the 8th century, Khazars dominated the Crimea (650–c. 950), and even extended their influence into the Byzantine peninsula of Cherson until it was wrested back in the 10th century. Khazar and Farghânian (Φάργανοι) mercenaries constituted part of the imperial Byzantine Hetaireia bodyguard after its formation in 840, a position that could openly be purchased by a payment of seven pounds of gold.