Origins and Birth in Exile
Tiberius was born in 705 AD at Phanagoria, an ancient city on the Taman Peninsula situated within the territory of the Khazar Khaganate. His father was the exiled Byzantine emperor Justinian II, a scion of the Heraclian dynasty who had ruled in Constantinople from 685 to 695 AD before being mutilated, deposed, and banished to Cherson in the Crimea. His mother was Theodora of Khazaria, sister of Busir Glavan, the Khagan of the Khazars. Justinian had escaped detention at Cherson, found sanctuary among the Khazars, and married the Khagan's sister around 703 AD. She took the Christian name Theodora, deliberately evoking the memory of the renowned sixth-century empress. When diplomatic maneuvers and bribes from the usurper Tiberius III prompted Khagan Busir to contemplate betraying Justinian to Constantinople, the exiled emperor fled westward to seek the support of Khan Tervel of Bulgaria. Justinian was compelled to leave his pregnant wife behind in Phanagoria under Khazar protection, where she soon gave birth to a son who was given the imperial name Tiberius.
Sources: head-1972, bury-1889, treadgold-1997
Elevation as Co-Emperor
In the late summer of 705 AD, Justinian II regained the Byzantine throne after leading a Bulgar and Slav force to Constantinople and infiltrating the city through a disused aqueduct conduit beneath the land walls. Having ousted and captured Tiberius III, Justinian moved swiftly to consolidate his restored authority and secure the imperial succession. He dispatched a fleet across the Black Sea to escort Empress Theodora and their infant son from Khazaria to the capital. Although a severe storm wrecked several vessels, the mother and infant were safely transported to Constantinople under an escort squadron commanded by the patrician Stephanos. Upon their arrival in late 705 or early 706 AD, Justinian celebrated a grand triumph. Patriarch Cyrus performed coronation ceremonies in the Great Palace, investing Theodora as Augusta and crowning the infant Tiberius as Augustus and co-emperor. By establishing his newborn son as co-ruler, Justinian sought to reaffirm the legitimacy of the Heraclian dynasty following a decade of political instability.
Sources: head-1972, bury-1889, treadgold-1997
Nominal Rule and Dynastic Presentation
The nominal reign of Tiberius lasted from his coronation in 706 AD until his death in late 711 AD. Because he remained an infant and toddler throughout these years, Tiberius exercised no personal governance. The supreme direction of the Byzantine state rested entirely with his father, Justinian II. Nevertheless, the child Augustus fulfilled an indispensable ideological role within the imperial system. Roman constitutional practice favored designating an heir as Augustus to project institutional continuity and discourage ambitious commanders from mounting revolts. Tiberius's status as joint ruler was broadcast widely across the empire through imperial coinage. Solidi and bronze issues struck at Constantinople, Ravenna, and Rome depicted Justinian II and the smaller figure of Tiberius standing together on the reverse, each wearing the imperial crown and chlamys while holding a patriarchal cross or globus cruciger between them. This numismatic imagery presented an unbroken Heraclian succession to Byzantine subjects and neighboring powers.
Sources: head-1972, bury-1889, treadgold-1997
Imperial Administration and Court Politics
Throughout the period of joint rule, administrative acts, official decrees, and liturgical invocations formally cited both Justinian II and Tiberius as emperors. In court ceremonies, the young co-emperor served as a living symbol of legitimate imperial majesty. In 710 AD, when Pope Constantine visited Constantinople to resolve differences regarding the canons of the Quinisext Council, the young Tiberius joined members of the Byzantine Senate and senior clergy in greeting the pontiff outside the city before escorting him to meet Justinian. Beneath the surface of public pageantry, however, Justinian II pursued severe reprisals against the political factions, commanders, and civil servants who had participated in his earlier deposition or served the usurpers Leontius and Tiberius III. The child Tiberius was raised in the imperial palace under the supervision of his mother Theodora and his paternal grandmother Anastasia. Justinian's uncompromising punishments and heavy exactions alienated broad segments of the military and the populace, undermining dynastic stability.
Sources: head-1972, bury-1889, treadgold-1997
Foreign Affairs and Frontier Crises
Tiberius's maternal heritage embodied an alliance between the Byzantine Empire and the Khazar Khaganate, linking Constantinople with the steppe realm north of the Black Sea. Relations with the Bulgarian Khanate also began cordially during the restoration, as Khan Tervel received the title of Caesar and substantial imperial gifts for assisting Justinian II. However, frontier security rapidly deteriorated during the joint reign. The Umayyad Caliphate launched devastating incursions into Anatolia, culminating in the capture of the fortress of Tyana in 708 AD after an extensive siege. In the west, imperial punitive actions alienated Italy, where a Byzantine naval expedition sacked Ravenna in 709 AD. The most catastrophic diplomatic failure occurred when Justinian dispatched repeated punitive naval expeditions to Cherson in the Crimea to punish its inhabitants for earlier hostilities. These heavy-handed assaults alienated both the Crimean provincials and their Khazar protectors, sparking the rebellion that sealed the fate of the Heraclian house.
Sources: head-1972, bury-1889, treadgold-1997
Religious Culture and Court Symbolism
The court milieu surrounding the infant Tiberius was shaped by intense Christian imperial piety. Justinian II was noted for framing his monarchy in terms of direct devotion to Christ, being the first emperor to place the bust of Christ Pantokrator upon imperial gold coinage during his initial reign. In his second reign alongside Tiberius, this religious iconography persisted: gold solidi featured Christ the King of Kings on the obverse, while the co-emperors on the reverse held symbols of divine sovereignty. The court emphasized sacred relics as protective talismans for the monarchy. Tiberius was provided with valuable reliquaries and pendants containing fragments of holy items, intended to preserve the child prince from physical harm and spiritual danger. When political collapse threatened the capital in 711 AD, the imperial family sought refuge at Blachernae, trusting in the protective aegis of the Virgin Mary, the traditional guardian of Constantinople.
Sources: head-1972, bury-1889, treadgold-1997
Assassination and Extinction of the Heraclians
In late 711 AD, imperial troops and naval forces stationed in the Crimea revolted under the leadership of the exiled general Bardanes, who took the regnal name Philippikos. Supported by the Khazars, the insurgent fleet sailed directly to Constantinople while Justinian II was absent in Bithynia. The capital surrendered to Philippikos, and Justinian was captured near Damatrys and executed in late 711 AD, his severed head brought to the city as confirmation of his death. Following news of the emperor's demise, the dowager empress Anastasia fled with her six-year-old grandson Tiberius to the Church of the Theotokos at Blachernae to seek sanctuary. The child grasped the holy altar with one hand, held relics of the True Cross in the other, and wore sacred amulets about his neck. Philippikos dispatched two officers, the patrician Mauros and John Strouthos, to capture the boy. While Mauros hesitated before Anastasia's entreaties, John Strouthos pried Tiberius away, stripped his religious amulets, and dragged him to the porch of the nearby chapel of Saint Callinicus, where the child co-emperor was butchered. Tiberius's death ended the Heraclian dynasty, which had occupied the imperial throne since Heraclius took power in 610 AD. Years later, during the reign of the Umayyad caliph Hisham, an imposter claimed to be Tiberius, illustrating the enduring memory of the murdered boy.
Sources: head-1972, bury-1889, treadgold-1997
References
- Justinian II of Byzantium. pp. 110-113, 148-151
- A History of the Later Roman Empire from Arcadius to Irene, 395 A.D. to 800 A.D., Volume 2. pp. 360-366
- A History of the Byzantine State and Society. pp. 341-345, 348-349