Hellenistic Tamiathis became a Christian bishopric, a suffragan of the Metropolitan see of Pelusium, the capital of the Roman province of Augustamnica Prima, to which Tamiathis belonged. Its bishop Heraclius took part in the Council of Ephesus in 431. Helpidius was a signatory of the decree of Patriarch Gennadius of Constantinople against simony in 459. Bassus was at the Second Council of Constantinople (553). In a letter from Patriarch Michael I of Alexandria read at the Photian Council of Constantinople (879), mention is made of Zacharias of Tamiathis, who had attended a synod that Michael had convened in support of Photius. Later bishops too of Tamiathis are named in other documents.