The Metropolis of Nafpaktos and Agios Vlasios (Greek: Ιερά Μητρόπολις Ναυπάκτου και Αγίου Βλασίου) is a metropolitan see of the Church of Greece.
[1][2] Like the rest of Illyricum, Nafpaktos depended on the pope of Rome until 733, when Leo III the Isaurian annexed it to the Patriarchate of Constantinople.
[5] It is thus that the see appears in the sources from the 9th century on as "Nafpaktos of Nicopolis" (μητρόπολις Ναυπάκτου Νικοπόλεως), counting initially eight suffragans covering all of Epirus: Vonditsa, Aetos, Acheloos, Rogoi, Ioannina, Photike, Hadrianopolis, Buthrotum.
In the Escorial Taktikon of the early 970s, the bishopric of Chimara has been added, and during the 11th century, two further sees, Kozyli and Arta were established under Nafpaktos.
[2][8] Under its metropolitan, John Apokaukos, the see of Nafpaktos gained in importance and headed the local synod for the southern half of the Epirote domains, but was soon overshadowed by the Archbishopric of Ohrid under the energetic Demetrios Chomatenos.