Busir or Busir Glavan (in Greek, Ibouzir or Ibousiros Gliabanos, Khagan of the Khazars in the late 600's and early 700's CE. Khagan, alternatively spelled Chagan, Qaqan etc. ... The site of the Khazar fortress at Sarkel. ...

In 704 Justinian II, who had been exiled at Chersones for nine years, arrived at Busir's court. Busir, perhaps seeking to use him in his political maneuverings with the Byzantine Empire, welcomed Justinian and gave him his sister in marriage (the woman's Khazarian name is unknown, but she took the baptismal name of Theodora.) Busir provided the couple with funds and a house in Phanagoria. Justinian II, known as Rhinotmetus (the Split-nosed) (669-711) was Byzantine emperor from 685 to 695 and again from 704 to 711. ... Tauric Chersonesos, Greek Χερσονασος (Chersones, Khersones, Korsun, Russian: Херсонес) was the Greek settlement founded approximately 2500 years ago in the southwestern part of Crimean (Taurian) Peninsula. ... The Byzantine Empire is the term conventionally used to describe the Greek-speaking Roman Empire during the Middle Ages, centred at its capital in Constantinople. ... Language spoken by the medieval Khazar tribe. ... Ancient Greek colony on the penninsula between the Black Sea and the Azov, roughly on the site of modern Tmutarakan. ...

However, the winds of realpolitik soon shifted, and the new emperor, Tiberius III, offered Busir a substantial bounty for his brother-in-law's head. Busir dispatched two agents, Balgitzin and Papatzys, to kill Justinian, but the latter was warned by his wife, who bribed the assassins' slaves to learn the nature of their mission. Turning the table on his would-be killers, Justinian murdered the pair after a banquet and fled Phanagoria by ship, seeking aid from Khan Terval of Bulgaria, with whose help he retook Constantinople. Tiberius III (d. ... In the account of Theophanes, Balgitzin was the Khazar tudun of Phanagoria during the sojourn of Justinian II in that town. ... In the account of Theophanes, Papatzys was the Khazar tudun of Kerch during the sojourn of Justinian II in Phanagoria. ... Khan Tervel or Tarvel, or Terval, or Terbelis in some Byzantine sources, was the khan of the Bulgars from 700 or 701-718. ...

Busir now attempted to make peace with Justinian, sending Theodora to Constantinople. He later became involved with, possibly instigating, a revolt by Justinian's officers in the Crimea, which led ultimately to the crowning of Bardanes as emperor and the death of Justinian in 711. The Crimea (officially Autonomous Republic of Crimea, Russian transliteration: Avtonomnaya Respublika Krym, Russian: Автономная Республика Крым, Ukrainian: Автономна Республіка Крим, , pronounced cry-MEE-ah in English) is a peninsula and an autonomous republic of Ukraine on the northern coast of the Black Sea. ... Philippicus, Eastern Roman emperor, 711– 713, was the son of the patrician Nicephorus, and became distinguished as a soldier under Justinian II. His proper name, which indicates his Armenian origin, was Bardanes. ...