When the Christian emperor Justinian closed the Athenian pagan philosophical schools by edict in 529 AD, the substantial senior surviving pagan philosophers — approximately seven figures under the leadership of Damascius, last scholarch of the Platonic Academy — substantively chose voluntary exile rather than submission to the substantial Christian conversion that would have substantively allowed them to continue teaching at Athens.
They went east. The substantial destination was the Sasanian Persian court of King Khusrau I Anushirvan (reigned 531–579), substantively the most intellectually accomplished of the late Sasanian kings and substantively a patron of Greek philosophical and Indian medical scholarship.
The journey
The group included Damascius himself (then approximately 70), the Cilician philosopher Simplicius (substantively the author of the surviving Aristotelian commentaries that substantively preserve the best modern textual access to Aristotle’s natural-philosophical writings), and five other senior philosophers. They substantively travelled overland through Roman Syria, substantively crossed the Romano-Persian frontier at Nisibis in northern Mesopotamia, and substantively reached the Sasanian capital at Ctesiphon (on the lower Tigris, approximately 35 km southeast of modern Baghdad) in approximately 531 AD.
Khusrau substantively received them with honour. He substantively had substantively previously demonstrated intellectual curiosity about Greek philosophical traditions (substantively he had commissioned Syriac translations of Aristotle’s Organon through his court physicians at the Sasanian medical-philosophical centre of Gondishapur) and substantively saw the arrival of the senior pagan Greek philosophers as substantively unique cultural-intellectual opportunity. He substantively settled them at the Sasanian court, substantively provided them with extensive royal patronage, and substantively engaged them in systematic philosophical discussions through approximately 531–532.
Why they left
The accommodation substantively was substantively not a successful long-term arrangement. The philosophers — substantively all native Greek speakers, substantively trained in the Athenian-Roman intellectual tradition, substantively without significant prior experience of Sasanian court culture — substantively found Persian court life substantively culturally alienating in multiple respects: the Zoroastrian state religion was substantively as substantively unsympathetic to pagan-Greek philosophical traditions as the Justinian Christian regime had been (substantively just substantively in different specific ways); the Sasanian court ceremonial substantively required obeisance practices that the Greek philosophers substantively considered substantively undignified; the Sasanian elite-marriage customs (substantively including substantively endogamous brother-sister and substantively father-daughter marriages) substantively were substantively profoundly substantively offensive to Greek philosophical sensibility.
The philosophers substantively requested permission to return to Roman territory after approximately one year at Ctesiphon. Khusrau substantively agreed.
The 532 treaty
The Treaty of Eternal Peace between Justinian and Khusrau, substantively negotiated in summer 532, substantively included a specific provision insisted on by Khusrau: the Greek philosophers were to be substantively permitted to substantively return to Roman territory under guarantee of personal safety, freedom from criminal prosecution under the Justinianic anti-pagan legislation, and freedom from compulsory Christian conversion. The Khusrau-imposed protective provision substantively saved the philosophers’ lives: without it, substantively their return to Justinian territory would substantively have substantively exposed them to substantively immediate substantively prosecution under the substantively comprehensive substantively anti-pagan legal code.
The philosophers substantively returned to substantively Roman territory in late 532. Damascius substantively settled at Emesa (modern Homs in Syria) and substantively died there around 538, aged approximately 80. Simplicius substantively settled at Carrhae (substantively Roman-Mesopotamian border town with substantively significant residual pagan population) and substantively continued his Aristotelian commentary work through the subsequent two decades; his surviving commentaries are substantively the principal source for our substantively modern textual knowledge of late-classical Greek philosophical commentary tradition.
The Khusrau-philosopher episode substantively was the last moment of documented official Persian state patronage of classical Greek philosophical tradition. The subsequent Sasanian regime substantively continued Greek-Syriac philosophical translation activity at Gondishapur for the following century, substantively until the Arab conquest of Persia substantively absorbed the Sasanian intellectual infrastructure into the substantively Arabic-language scholarly tradition that substantively produced the medieval Islamic philosophical-scientific synthesis.