The conquests of Justinian

On 1 July 527, Justinian was crowned emperor of Byzantium. It was only several centuries later that this empire became known as the ‘Byzantine Empire’; in Justinian’s day, it was simply the Eastern Roman Empire.

At the time, this Empire was still a great Mediterranean power, known for the size of its army and its fleet and for the wealth of its cities, especially the capital.

Justinian was an ambitious ruler and wanted to restore the old Roman Empire. This meant conquering the West, which over the previous century had slipped from the Caesars’ grasp. Despite a reign marked by a severe plague epidemic, the ‘Justinian plague’, the emperor won many victories.

In the Balkans, Justinian reinforced the border fortifications needed to counter incursions by nomadic peoples such as the Avars and the Bulgars. He thus strengthened Byzantium’s religious and economic influence over this large region.

In the east, Justinian inherited a protracted war with the powerful Persian Empire marked by a succession of successes and failures. In 532 the two empires signed a ‘perpetual peace’... but it did not last long. In 541 the Persians took the city of Antioch, but they never really managed to consolidate their domination. Despite 20 years of almost permanent warfare, the border between the two empires changed little.

This was not the case in the West. In 533, Belisarius, the best Roman general, led an army into the heart of the Vandal Kingdom and took Carthage, its capital. He quickly went on to capture Corsica and Sardinia and re-established imperial authority over a large part of the African coastline, although many revolts would follow.

In 536, to the north of the Mediterranean, Belisarius led an offensive against the Ostrogothic Kingdom. He took Rome, then Milan and finally Ravenna in 540. But the conflict against the Persians resumed in the east, allowing the Ostrogoths to regain the initiative. The second ‘Gothic War’ lasted for many years, until the Romans finally triumphed in 552 at the Battle of Vesuvius. The war ruined the Italian peninsula. Rome, taken and recaptured at least four times in 20 years, saw its population collapse: there were now only 30,000 inhabitants, whereas Rome in the second century had been home to around a million people.

In 552, Justinian took advantage of internal disturbances in the Visigothic Kingdom to reconquer part of the southern Iberian Peninsula, but imperial authority there remained very fragile.

By the end of his reign in 565, Justinian had not succeeded in restoring the Roman Empire to its former glory, but he had established Byzantium’s domination over the Mediterranean sea.