Most probably its people belonged to the domain of the then more famous Harran-Carrhae, between which and Samosata (on the Euphrates) Urhai lies midway (some 25-30 m.
At such times, therefore, it included such towns as Harran (Carrhae), Nisibis, Sarug, Zeugma-Birejik, Resaena, Singara, Tigranocerta, Samosata, Melitene.
Diocletian's persecution secured the martyr's crown for the Edessenes Shamona, Guria (297), and Ilabbib (309), and shortly thereafter Lucian " the martyr," who though born at Samosata received his training at Edessa; but the bishop Qona, who laid the foundations of " the great church " by the sacred pool, somehow escaped.
Thoros applied for help to Baldwin, brother and successor of Godfrey of Bouillon in the First Crusade, who in 1098 took possession of the town and made it the capital of a Burgundian countship, which included Samosata and Sari-1g, and was for half a century the eastern bulwark of the kingdom of Jerusalem.'
He appears in connexion with the dispute in the church of Antioch between Paul of Samosata, who had been deprived of his bishopric by a council of bishops for heresy, and his successor Domnus.