Justin II was the nephew of Justinian I. Byzantium was beset by its enemies; but the Emperor Justin II, unshakeable in his self-confidence, believed that with wisdom and courage those enemies could be scattered. He gave proof of this belief within a week of his accession, when he received an embassy from the Avars, a race of probably Tartar origin that had first appeared in the West only a few years before. His uncle had characteristically agreed to pay them an annual subsidy in return for an under-taking to protect the frontiers; this payment Justin now refused. Over the following year he took a similar line with the other recipients of Justinian's bounty; including King Khushru I himself. Such firmness much increased his popularity; it soon revealed, however, that his uncle's money had been well-spent.
The race responsible for the worst disaster of Justin's reign was however one which had never received Byzantine protection money. The Lombards were a Germanic people who had slowly drifted southwards into what we should now call Austria. Entering Italy early in 568, they skirted Ravenna and encountered little resistance except at Pavia. Their King, Alboin, advanced no further than Tuscany, but many of his nobles pressed on further to set up independent duchies in Spoleto and Benevento. Thus the Lombards invaded Italy not as raiders but as permanent settlers. They intermarried with the Italians, adopted their language, absorbed their culture and doubtless intended to make the whole peninsula their own. Their avoidance of Ravenna and the cities of the Venetian lagoon was probably due to their lack of numbers; Naples, Calabria and Sicily also remained in imperial hands. They were thus in no sense destroyers of Justinian's achievement; they merely introduced a powerful new element into Italy.
Justin could take no action against the Lombard tide; he was fully occupied with the Avars. In 568 they had burst into Dalmatia in a frenzy of destruction; but after three years the Byzantines were obliged to seek a truce. The ensuing treaty cost Justin 8o,ooo pieces of silver, far more than the original subsidy. That same year, 571, saw a dangerous development in the East, when the Armenians rebelled against King Khushru and appealed to Justin as fellow-Christian for support, a request which he could not possibly ignore. Early in 572 the Persian War was resumed. The following year the Persians seized Dara on the Tigris, an important Christian bishopric, simultaneously ravaging Syria - whence they are said to have returned with no fewer than 292,000 captives. Of these, 2,000 exquisite Christian virgins had been personally selected by Khushru; but the maidens, reaching a river; sought permission to bathe, distanced themselves from the soldiers on grounds of modesty and then, rather than face the loss of religion and virtue together, drowned themselves.
By this time the Emperor had begun an open persecution of the monophysites. There were no executions or tortures, but monks and nuns were driven from their monasteries and convents, and the monophysite clergy were no longer recognized. This may have been due to Justin's rapidly growing insanity. Often subject to fits of violence, he would attack anyone who approached and try to hurl himself from the windows, which were fitted with bars for his protection. Sophia, now Supreme, bought a year's truce with Khushru; but at the end of 574, she persuaded her momentarily lucid husband to raise a general named Tiberius to the rank of Caesar; the two then acted as joint Regents; and when Justin died in 578 Tiberius was his uncontested successor.