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.
[1] 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.
[6] The priest Abraham 'of the great church of Aksondnokre' was among the signatories of the acts of the synod of Acacius in 486, on behalf of the bishop Joseph of Rai.
[10] The bishop Mark of Beth Bgash was appointed metropolitan of Rai by the patriarch Yohannan III immediately after his consecration on 15 July 893.
[11] The metropolitan ʿAbd al-Masih of 'Hulwan and Rai' was present at the consecration of ʿAbdishoʿ II in 1075, and died at an unknown date during his reign.