City in Mesopotamia and important center of early Syriac Christianity. Birthplace, among others, of Ephrem and site of the School of Nisibis. The Syriac name Nṣibin can be traced back to Assyrian Naṣibīna, while the name Ṣobā, based on identification with biblical Ṣōbā (2 Sam. 8.1), seems to be of relatively late origin. Nisibis is located on a main east-west route in an area watered by the Çağçağ river (ancient Mygdonius), a tributary of the Khabur, which emerges from Mount Izla, or the southern slopes of Ṭur ʿAbdin, on to the Mesopotamian plain just north of Nisibis. A border town in Turkey today opposite Syrian Qamishli, Nisibis was a frontier town in ancient times in an area contested between the Roman and Persian empires. Along with the monasteries on Mount Izla, it was also in an area where the spheres of influence of the E.-Syr. and W.-Syr. churches met. E. Syriacs, predominant at first, were later outnumbered by W. Syriacs among the dwindling population of Christians in the town.

Legends attribute the evangelisation of Nisibis to Addai or to his disciples Aggai and Mari. The first attested bp. of the city is Yaʿqub of Nisibis (308/9 – after 338) who attended the Council of Nicaea and is commemorated, along with his successors Babu and Vologeses (d. 361/2), by his pupil Ephrem in his Carmina nisibena. After its cession by Jovian to Shapur II in 363, Nisibis remained more or less permanently in Sasanian hands until the Islamic conquest in 640.

At the Ch. of E. synod of 410 Nisibis was made the metropolitan see of Beth ʿArbaye with Arzun, Qardu, Beth Zabdai, Beth Rahimai, and Beth Moksaye as suffragans. The episcopate of Barṣawma of Nisibis (ca. 450–91) saw the establishment of the School of Nisibis under the leadership of Narsai. Under Islamic rule, with the disappearance of the Roman-Persian border, Nisibis gradually lost its strategic, as well as commercial, importance. Later occupants of the see include Eliya of Nisibis, Ishoʿyahb bar Malkon (before 1222–47?), and ʿAbdishoʿ bar Brikha. When, between 1482 and 1489, Syr. Orth. Patr. Ignatius Sobo of Ṭur ʿAbdin attempted to gain control of the churches of St. Jacob and St. Domitius, the E. Syriacs were still numerous enough to resist this move. The E. Syr. see of Nisibis, Chald. by then, was finally suppressed in 1616.

The first appearance of a Syr. Orth. bishop of Nisibis (Abraham, 631) may be connected with the Roman advances made in the area under Emperor Heraclius. Bishops specifically for Nisibis are known from the end of the 8th cent. until the 11th cent., but in the 12th cent. ‘Nisibis’ is found among the titles of the metropolitans of Mardin. From then on, no resident Syr. Orth. bp. of Nisibis is attested until 1860.

O. H. Parry found 300 Muslim, 150 Jewish, and 30 Syrian families in the town on a visit in 1892. The Christian community in the town, reported to number 200 families in 1915, disappeared after the First World War, although the presence of three Christian families after the Second World War is mentioned by Anschütz.

Little remains of the Christian past in Nisibis, but the Church of St. Jacob, incorporating the baptistery built in 359 and the crypt with the tomb of Yaʿqub of Nisibis, is still maintained as a church (Syr. Orth. since 1865). Excavations have been under way since 2000 in the area to the south of the church, the site of the original cathedral built by Yaʿqub of Nisibis in 312–20. The church of St. Febronia (4th cent. martyr) is now the Mosque of Zayn al-ʿĀbidīn.

See Fig. 92.