When Justinian ascended the throne (527), the empire had reasonably well-defined frontiers: the Danube, the Euphrates, and the Arabian and Egyptian deserts. They were defended by powerful frontier fortresses, such as Singidunum, Dara and Edessa. Such threats as there were, the Sassanian Persians in the east, the Bulgars along the lower Danube, and the desert tribes, were more or less contained. Internally there were the rivalries of the circus factions, but religious divisions were more serious. The emperor and the Church at Constantinople were caught between those who valued ecclesiastical unity and the link with the papacy enshrined at the council of Chalcedon (451) and those who favoured an independent Byzantine Church. The latter had been in the ascendant since c. 484, when the Acacian schism separated the Churches of Rome and Constantinople. Even before coming to the throne Justinian worked for communion with Rome, which was achieved in 518. This reorientation implied an increased interest in the west, largely dominated by Germanic tribes which had adopted the Arian heresy. There was some discrimination against the native Catholic communities, and in North Africa under the Vandals outright persecution. Justinian saw himself as protector of the Catholic Church. In 533 he launched an expedition against the Vandals, and his commander, Belisarius, took Carthage, the Vandalic capital, and recovered the North African provinces. Next Justinian interfered in Ostrogothic Italy. In 535 Belisarius seized Sicily and invaded Italy. The key was Rome, which Belisarius took in 536. His successful defence of the city sapped Ostrogothic
Resistance, and he entered their capital of Ravenna in 540. The Ostrogoths were confined to the Po valley.
These relatively easy victories were to be tested over the next decade. The Sassanian king of kings, Chosroes I (531-79), sacked Antioch in 540, and his armies captured Petra which commanded access to the Black Sea and control of Lazica. In 544 the city of Edessa beat off a Persian attack and a truce was concluded. Both sides were suffering from the effects of the bubonic plague which had struck in 541/2. The loss of life at Constantinople was calamitous. The administration and the economy were paralysed. The Ostrogoths recovered most of Italy and the Slavs, massed along the Danube, raided deep into the European provinces of the empire. Justinian's government slowly began to recover its equilibrium. In 550 the European provinces were cleared of Slav raiders. In 552 Narses invaded Italy with an army depending heavily on contingents recruited beyond the Danube from the Herules, the Gepids and Lombards. The Ostrogoths were overwhelmed and Italy was restored to the empire. Meanwhile an expedition, despatched in 550, recovered southern Spain from the Visigoths, as well as the North African coast around Septem (Ceuta). Along the eastern frontier Petra was recovered from the Sassanians in 551 and with it control of Lazica. In the desert war the Ghassanids, an Arab tribe allied to the Byzantines, bested the Lakmids, who were clients of the Sassanians. In 562 a peace was concluded between Persia and Byzantium, designed to last for fifty years. Among other things it regulated cross-border trade, trade routes being an element in Byzantine-Sassanian rivalry. The Byzantines were dependent on these for raw silk to feed their industry which was centred on Berytus.
to heavy investment in fortifications the Danube frontier held, but there was intense pressure from the tribes, Slavs and others, who crowded along it. To counter this, Justinian turned to the Avars, recently arrived from central Asia and settled to the north of the Crimea. It was a miscalculation. After Justinian's death the Avars destroyed the Gepids in 567, pushed the Lombards into Italy, and intensified Slav raiding of Byzantine territories. It contributed to the eventual disintegration of Justinian's empire which was already apparent in the ecclesiastical field, where independent Churches were coming into being in Syria and Egypt. It has been said that Justinian's reign witnessed a belated attempt to unify a far-flung Empire that was gradually losing its cohesion'.
M. Angold
World History
