Oriental Orthodoxy is the faith of those Eastern Christian Churches that recognize only the first three ecumenical councils the First Council of Nicaea, the First Council of Constantinople and the First Council of Ephesus. They rejected the dogmatic definitions of the Council of Chalcedon held in 451 AD in Chalcedon. Hence, these Oriental Orthodox Churches are also called Old Oriental Churches, Miaphysite Churches, or the Non-Chalcedonian Churches, known to Western Christianity and much of Eastern Orthodoxy as Monophysite Churches (although the Oriental Orthodox themselves reject this description as inaccurate, having rejected teachings of both Nestorius and Eutyches). These churches are in full communion with each other but not with the Eastern Orthodox Churches. Slow dialogue towards restoring communion is in progress since mid-20th century.
Contributions by Orthopraxia, Michael Hardy, and Codex Sinaiticus.