This war, which the emperor undertook with such a light heart, was destined to last no less than nineteen years (572-591), and to drag on into the reigns of two of his successors. [Sidenote: Persian War of Justin.] It was quite as inconclusive, and quite as costly in men and money, as had been the previous struggle in the reign of Justinian. On the whole, the Romans lost no territory during its course. Their farthest frontier stronghold of Daras was the only place of importance that fell into Persian hands in the earlier years of the war, and the secondary fortress of Martyropolis, in the Armenian Highlands, the only loss of its later years. Both were destined to be recovered, and the second Roman line of defence, based on Edessa and Amida, held good. If the armies of Chosroes once succeeded in penetrating into Syria, it is only fair to add that the imperial troops made several incursions into the Persian border-lands of Arzanene and Corduene. It was not so much by the loss of fortresses or the ravaging of territory that the war was harmful to the empire, as by the long, fruitless drain of taxation that it brought about. Where the tax-gatherer of Justinian’s time had shorn the population close, the tax-gatherer of Justin’s was obliged to flay them, in order to wring out the necessary solidi. Having begun the war at his own pleasure, Justin found that he could not conclude it in a similar way. The Persians hoped to win by exhausting the empire’s resources, and were set on protracting the weary game. In the ninth year after his succession to the throne, Justin was seized with suicidal mania, and had to be placed in close restraint for all the rest of his life. On his first lucid interval he nominated as his colleague, and crowned as Caesar, a respectable military officer, named Tiberius Constantinus, who, in conjunction with the empress Sophia, acted as regent for the demented emperor till 578. Sophia, a proud and restless woman, kept most of the power in her own hands, for Tiberius was not of a pushing or ambitious disposition. His accession to power made little or no difference in the policy of the court, which was still guided by the empress. While Justin saw the Balkan peninsula ravaged by the Avars, and the Mesopotamian frontier beset by the Persians, he was destined to suffer a still more grievous loss in another region of his empire. The Lombards, emigrating from the middle Danube, followed the track that the Ostrogoths had taken eighty years before, and threw themselves on the newly-recovered province of Italy, only fifteen years after it had been finally secured to the empire by the victories of Narses at Taginae and Casilinum. Their fortunes will be described in another chapter. Here it must suffice to say that ere the end of the reign of Justin II. they had torn two-thirds of the peninsula from the grasp of the East-Roman governors.