Byzantium once refused to adopt a Persian prince, and regretted it
Around 520 the Persian shah Kavad asked the Byzantine emperor to adopt his youngest son, to shore up the boy's claim. Constantinople would only adopt him as a barbarian, not a Roman. The insulted prince became Khosrow I, who later sacked Antioch and made his name a byword for kingship.
Khosrow was born around 512 to 514 in Ardestan in central Iran, the youngest son of Kavad I. Like other noble boys he would have begun school between five and seven, memorising Zoroastrian scripture much as a trainee priest did, before moving on to riding, archery and polo. His path to the throne was uncertain: older brothers had rival claims, and the Mazdakites, an egalitarian religious movement his father had once backed, supported his eldest brother Kawus. The failed adoption talks, in which a Byzantine official feared a Persian heir might one day claim the Roman throne, soured Khosrow on Constantinople for good.
He became King of Kings in 531 and, insecure at home, made the Perpetual Peace with Justinian in 532, receiving 11,000 pounds of gold. He then crushed the Mazdakites, defeated Kawus and executed conspirators including his uncle. In 540, prodded by envoys from Ostrogothic Italy and annoyed by Byzantium's Arab clients, he tore up the treaty, sacked Antioch and moved its people to Persia. Years of fighting over Lazica in the Caucasus ended in a fifty-year peace in 562, though war returned in 572 and lasted beyond his death.
His campaigns reached in every direction. Allied with the Göktürks, he destroyed the Hephthalites, the Central Asian power that had killed his grandfather Peroz in the previous century. In the south, his general Wahrez beat the Aksumites and took Yemen. When he died in 579, Sasanian rule stretched from Yemen to Gandhara, its widest since Shapur II.
At home he carried on his father's reforms, raising state revenue, building a professional army and founding or rebuilding cities and palaces. Art, science and philosophy flourished at his court. After his death he was remembered as Anushirvan, the Immortal Soul, and his name passed into Arabic as Kisra, a general title for Persian kings, much as Caesar became one in Rome.
Source: Khosrow I
