A metropolitan of Salmas named Joseph was one of the signatories of a letter of 1580 from Shemʿon IX Denha to pope Gregory XIII, and was presumably consecrated by his predecessor shortly after he became patriarch.
A metropolitan of Salmas named Ishoʿyahb, from Khosrowa, is mentioned together with the patriarch Shemʿon XIII Denha (1662–1700) in the dating formulas of manuscripts of 1667, 1678 and 1686.
This Mar Ishoʿyahb appears to have been given the reign-dates 1709–52 by Tfinkdji and Fiey because a metropolitan of the same name fled 'on account of the destruction of his diocese by Oz Beg' to the village of Seduh near Seert in 1751, 'where he long remained'.
Ishoʿyahb's flight to the Chaldean village of Seduh strongly suggests that he was a Catholic bishop dependent on Joseph III, and it is therefore probable that the two men should be identified.
The decisive shift to Catholicism seems to have been made in the last quarter of the eighteenth century, thanks to the efforts of the metropolitan Ishoʿyahb Shemʿon (1777–89), who entered into communion with the Catholic Joseph line at Amid, bringing with him the majority of the East Syriacs of the region.
His appointment was resisted by a party in the Salmas district, who wanted as their bishop the priest Isaac, a nephew of the late metropolitan Ishoʿyahb Shemʿon.
They sent Isaac to the Nestorian patriarch Shemʿon XVI Yohannan, who consecrated him bishop of Salmas at Qudshanis, giving him the name Ishoʿyahb Melchisedec.
During the last years of his reign the Chaldean bishop Peter Shawriz, ordained for Seert in 1801, resided in the Salmas district, where he died in 1831.
According to the epitaph on his tombstone in the cemetery of Khosrowa, he was the son of Ishoʿyahb Shemʿon's brother the priest Isaac, who died in 1800, and was styled 'metropolitan of Salmas and administrator of Adarbaigan'.
Possibly because of his previous association with the Nestorian patriarch, but principally because he was already elderly, Melchisedec was given assistance in his episcopal duties.
After Nicholas Zayʿa became patriarch in 1839, Melchisedec seems to have been left temporarily without supervision, but a second coadjutor, Giwargis Augustine Barshina, was consecrated for the diocese in 1848.
He was succeeded in 1894 by Isaac Yahballaha Khudabakhash, who was born on 18 October 1859 in Khosrowa, educated at the college of the Propaganda, and ordained a priest on 28 February 1887.
Isaac was succeeded in 1910 by Peter ʿAziz, who was born in Mosul on 6 April 1866, educated at the college of the Propaganda, and ordained a priest in 1890.
After his departure the Chaldean diocese of Urmi, vacant since the end of the First World War, became a metropolitan see, and was united with the see of Salmas in 1930.
Because of its geographical proximity the Chaldean diocese of Salmas also included the village of Gawilan, in the extreme north of the Anzel district, which had a significant Catholic community.
Youel Baaba, in a recently published bilingual book, mentions several other villages in the Salmas district with East Syriac populations: Balarur, Karilan, Kolamar, Kohnashahr, Koysan and Malham.