Metropolis of Derkoi

The Metropolis of Derkoi (Greek: Ἱερὰ Μητρόπολις Δέρκων) is a residential see of the Orthodox Church subject to the Ecumenical Patriarch of Constantinople and situated in the Istanbul suburb of Yesilköy (historically San Stefano). The cathedral is that of St. Parakevi in Therapia (Tarabya). The metropolitan is a member of the Patriarchal Synod. The present Metropolitan is Apostolos Daniilidis.

The village of Derkos/Derkoi (modern Durusu or Terkos) is attested since Classical Antiquity, but Emperor Anastasius I (r. 491–518) raised it to the status of a city and rebuilt it as a forward stronghold for the defence of Constantinople. Probably at the same time it was created as an episcopal see ("Bishopric of Derkoi and Chele", Επισκοπή Δέρκων και Χήλης). In the first half of the 6th century, the town and the see were known as a stronghold of the Monophysites.

The see was a suffragan of the metropolis of Heraclea until the 10th century, when it became an archbishopric. Bishop Gregory I took part in the Second Council of Nicaea in 787; Macarius I participated in the council of 879, Archbishop Constantine participated in the anti-Jacobite council of 1030, and an unnamed archbishop took part in the Council of Blachernae against John Italos in 1082. In 1166, Archbishop John II tried repeatedly, but without success, to have his see moved to nearby Philea. An archbishop Michael is attested in a latter of 1177 to the Catholicos of Armenian Cilicia Gregory IV the Young, and an archbishop Gregory in a synod in February 1197.

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