most commonly known in Persian as Anooshiravan also spelled Anushirvan, meaning the immortal soul, also known as Anooshiravan the Just, was the favourite son and successor of Kavadh I (488531), and the most famous and celebrated of the Sassanid Kings. He laid foundations of many new cities and magnificent palaces, trade roads were repaired and new bridges and dams were built. During Khosrau I's ambitious reign art and science flourished in Persia and the Sassanid empire was in its peak of glory and prosperity. His rule preceded by his father's and succeeded by Khosrau II's (590628) reign altogether is considered the Second golden era in the history of the Sassanid empire.
According to one account, Khosrau I was Kavadh I's son through a peasant girl, and was originally considered unworthy of inheriting his father's throne. His brothers contested his claim, so Khosrau I had them killed (ca. 532). He appears to have had a major influence over his father Kavadh I of Persia and helped him in the worst situations during the later years of his rule. He was apparently also behind many of his father's decisions.
According to the Roman Historian Procopius of Caesarea, Kavadh I tried to have his third son Khosrau adopted by the Eastern Roman emperor Justin I. in the mid-520s. This is the first time that Khosrau is mentioned in the sources. After Romans and Persians had failed to reach an agreement about the adoption, a new war began in 526 which was to last until 532.
At the beginning of his reign Khosrau I concluded an "eternal" peace with the Byzantine Emperor Justinian I (527565), who wanted to have his hands free for the conquest of Africa and Sicily. But (according to Procopius) his successes against the Vandals and Goths caused Khosrau I to begin the war again in 540.
He invaded Syria and carried the inhabitants of Antioch to his residence, where he built for them a new city near Ctesiphon under the name of "Khosrau-Antioch" or "Chosro-Antioch". During the next years he fought successfully in Lazica or Lazistan (Colchis) in the Lazic War, on the Black Sea, and in Mesopotamia.
The Romans, though led by Belisarius, could do little against him. In 545, an armistice was concluded, but the Lazic War went on till 557. At last, in 562, a peace was concluded for fifty years, in which the Persians left Lazica to the Romans, and promised not to persecute the Christians, if they did not attempt to make proselytes among the Zarathustrians; on the other hand, the Romans had again to pay subsidies to Persia.
Meanwhile in the east, the Hephthalites had been attacked by the Turks (Göktürks). About 560, Khosrau I united with them to destroy the Hephthalite Empire. In 567 he conquered Bactria, while he left the country north of the Oxus to the Turks. Many other rebellious tribes were subjected. About 570 the dynasts of Yemen, who had been subdued by the Ethiopians of Axum, applied to Khosrau I for help. The King sent a fleet with a small army under Vahriz, who expelled the Ethiopians. From that time till the conquests of Muhammad, Yemen was dependent on Persia, and a Persian governor resided here. In 572 a new war with Rome broke out about Armenia, in which Khosrau I conquered the fortress Daraa on the Euphrates, invaded Syria and Cappadocia, and returned with large booty. He was defeated by the Romans in a battle near Melitene in 575 (or 576). During the peace negotiations with the Emperor Tiberius II (578582), Khosrau I died in 579, and was succeeded by his son Hormizd IV (579590).
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