the elder son of Germanus (see the genealogical table prefixed to the life of Justinian I.), a general of great distinction and popularity in the army, but justly suspected by Justinian I. and Justin II., on account of his ambition and faithlessness. In A. D. 551 he held a command in the army against the Slavonians, and shared its defeat in the battle of Adrianople.
He was more fortunate against the Persians in Colchis, over whom he obtained a complete victory on the river Phasis (555), in consequence of which he was entrusted with the command in chief, which had been taken from Martinus. Some time after he discovered the secret designs of the khan of the Avars, who had sent an embassy to Constantinople under the pretext of making a treaty of alliance, and while their real object was the purchase of arms, and the stores which they were secretly sending into Avaria were consequently taken from them by Justin, who commanded on the Avarian frontiers (the Danube).
The accession of his cousin Justin proved fatal to him: they had made an agreement that, after the expected death of Justinian, the son of Germanus should be Caesar, while the other Justin, the son of Vigilantia, was to reign as Augustus.
But no sooner was the latter seated on the throne, than Justin, the subject of this article, was recalled from the Danube, and after having been detained a short time at Constantinople, was sent as governor (Dux and Augustalis) to Alexandria, where he was, however, treated like a prisoner, and, shortly after his arrival, treacherously assassinated while asleep. His murder caused several of his friends to conspire against the emperor, as is narrated in the life of Justin II. (Theophan. p. 198, 204-210, ed. Paris; Agathias, 2.18, 3.2, 17-23, 4.13-22; Procop. Bell. Goth.
3.32; Evagrius, 5.1, 2.)