First Council of Constantinople

The First Council of Constantinople (Latin: Concilium Constantinopolitanum; Ancient Greek: Σύνοδος τῆς Κωνσταντινουπόλεως) was a council of Christian bishops convened in Constantinople in AD 381 by the Roman Emperor Theodosius I. This second ecumenical council, an effort to attain consensus in the church through an assembly representing all of Christendom, except for the Western Church, confirmed the Nicene Creed, expanding the doctrine thereof to produce the Niceno-Constantinopolitan Creed, and dealt with sundry other matters. It met from May to July 381 in the Church of Hagia Irene and was affirmed as ecumenical in 451 at the Council of Chalcedon for Chalcedonian Christianity and the Second Council of Ephesus for the Oriental Orthodox Churches.

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