Christians in the Persian Gulf

Christians reached the shores of the Persian Gulf by the beginning of the fourth century. According to the Chronicle of Seert, Bishop David of Perat d'Maishan was present at the Council of Seleucia-Ctesiphon, around 325, and sailed as far as India. Gregory Bar Hebraeus, Chron. Eccles, 2.10 (v. 3, col. 28) indicates that David had earlier ordained one of the other bishops present at the Council. The monk Jonah is said to have established a monastery in the Persian Gulf "on the shores of the black island" in the middle of the fourth century. A Nestorian bishopric was established at Rev-ardashir, nearly opposite the island of Kharg, in Southern Persia, before the Council of Dadisho in AD 424.

Eastern Arabia was divided into two main ecclesiastical regions: Beth Qatraye (northeastern Arabia) and Beth Mazunaye (southeastern Arabia). Christianity in Eastern Arabia was blunted by the arrival of Islam by 628. Despite this, the practice of Christianity persisted in the region until the late 9th century.

From the fifth century onward the Persian Gulf fell under the jurisdiction of the Assyrian Church of the East. Christian sites have been discovered dating from that time until after the advent of Islam in the region at Failaka, Kharg, Jubail and the nearby settlements of Thaj, al-Hinnah and Jabal Berri, and Sir Bani Yas.

After the region fell under the reign of the Sasanian Empire in the early third century, many of the inhabitants in Eastern Arabia were introduced to Christianity following the eastward dispersal of the religion by Mesopotamian Christians. However, it was not until the fourth century that Christianity gained popularity in the region. This was, in large part, due to the persecution of Christians in Iraq and Iran under the reign of Shapur II starting in 339. Another factor in the growing influence of Christianity was the migration of Christian traders to the region who were looking to capitalize on the well-established pearl trade.

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