Ephrem was born at Nisibis on the eastern frontier of the Roman Empire, possibly to a pagan family, and was baptised in his youth. He served the bishops of Nisibis as a deacon and as head of the school of biblical exegesis there until the Persian conquest of the city in 363 forced him to flee west to Edessa.
At Edessa he founded the renowned 'School of the Persians' and lived as an ascetic, refusing priesthood and never accepting episcopal office. He composed hundreds of biblical commentaries, prose works, and especially metrical hymns in Syriac. His verse — taught to choirs of consecrated women whom he organised at Edessa — was used as the principal weapon against the elaborate heresies of his time (chiefly those of Bardaisan).
He died of plague while caring for victims in Edessa in 373. Some four hundred of his Syriac hymns survive, almost all his commentaries, and the great prayer that bears his name (the Prayer of St. Ephrem, said daily in Eastern monasticism throughout Lent). Pope Benedict XV declared him a Doctor of the Church in 1920 — the only Syriac-language Father so honoured.