In
Tabaristan (northern Iran), the diocese of Rai (Beth Raziqaye) is first mentioned in 410, and seems to have had a fairly uninterrupted succession of bishops for the next six and a half centuries. Bishops of Rai are first attested in 424 and last mentioned towards the end of the eleventh century. An East Syriac diocese was established in the Sassanian province of Gurgan (
Hyrcania) to the southeast of the Caspian Sea in the fifth century for a community of Christians deported from Roman territory. The bishop Domitian 'of the deportation of Gurgan', evidently from his name a Roman, was present at the synod of Dadishoʿ in 424, and three other fifth- and sixth-century bishops of Gurgan attended the later synods, the last of whom, Zaʿura, was among the signatories of the acts of the synod of Ezekiel in 576. The bishops of Gurgan probably sat in the provincial capital
Astarabad. The diocese of Rai was raised to metropolitan status in 790 by the patriarch Timothy I. According to
Eliya of Damascus, Gurgan was a suffragan diocese of the province of Rai in 893. It is doubtful whether either diocese still existed at the end of the thirteenth century. The last-known bishop of Rai, ʿAbd al-Masih, was present at the consecration of ʿAbdishoʿ II in 1075 as 'metropolitan of Hulwan and Rai', suggesting that the episcopal seat of the bishops of Rai had been transferred to Hulwan. According to the
Mukhtasar of 1007/08, the diocese of 'Gurgan, Bilad al-Jibal and Dailam' had been suppressed, 'owing to the disappearance of Christianity in the region'. == The Diocese of Rai ==