Early Christian centre

King Abgar holding the Image of Edessa.
See also: School of Edessa and Early centers of Christianity § Mesopotamia and the Parthian Empire
The precise date of the introduction of Christianity into Edessa is not known. However, there is no doubt that even before AD 190 Christianity had spread vigorously within Edessa and its surroundings and that shortly after the royal house joined the church.[16][better source needed]

According to a legend first reported by Eusebius in the fourth century, King Abgar V was converted by Thaddeus of Edessa,[17][better source needed] who was one of the seventy-two disciples, sent to him by "Judas, who is also called Thomas".[18] However, various sources confirm that the Abgar who embraced the Christian faith was Abgar IX.[19][20][21] Under him Christianity became the official religion of the kingdom.[22]

He was succeeded by Aggai, then by Saint Mari, who was ordained about 200 by Serapion of Antioch. Thence came to us in the second century the famous Peshitta, or Syriac translation of the Old Testament; also Tatian's Diatessaron, which was compiled about 172 and in common use until Rabbula, Bishop of Edessa (412–435), forbade its use. Among the illustrious disciples of the School of Edessa, Bardaisan (154–222), a schoolfellow of Abgar IX, deserves special mention for his role in creating Christian religious poetry, and whose teaching was continued by his son Harmonius and his disciples.[citation needed]

A Christian council was held at Edessa as early as 197. In 201 the city was devastated by a great flood, and the Christian church was destroyed. In 232 the relics of the apostle Thomas were brought from Mylapore, India, on which occasion his Syriac Acts were written. Under Roman domination many martyrs suffered at Edessa: Sharbel and Barsamya, under Decius; Sts. Gûrja, Shâmôna, Habib, and others under Diocletian. In the meanwhile Christian priests from Edessa had evangelized Eastern Mesopotamia and Persia, and established the first Churches in the Sasanian Empire. Atillâtiâ, Bishop of Edessa, assisted at the First Council of Nicaea (325). The Peregrinatio Silviae (or Etheriae) gives an account of the many sanctuaries at Edessa about 388.

As metropolis of Osroene, Edessa had eleven suffragan sees.[26] Michel Le Quien mentions thirty-five bishops of Edessa, but his list is incomplete.

The Eastern Orthodox episcopate seems to have disappeared after the 11th century. Of its Jacobite bishops, twenty-nine are mentioned by Le Quien (II, 1429 sqq.), many others in the Revue de l'Orient chrétien (VI, 195), some in Zeitschrift der deutschen morgenländischen Gesellschaft (1899), 261 sqq. Moreover, Nestorian bishops are said to have resided at Edessa as early as the 6th century.