Check.Church

Oriental Orthodoxy

Oriental Orthodox · 451–554 · Egypt, Syria, Armenia, Ethiopia, India

The churches of Alexandria, Syria, Armenia, and their heirs (Ethiopian, Eritrean, Malankara) did not receive Chalcedon's 'in two natures' definition, holding the Cyrillian one-incarnate-nature formula; both sides reject Eutyches and Nestorius alike. Use 'Miaphysite,' never 'Monophysite.'

Oriental Orthodoxy was formed between 451 and 554, as a process rather than a single event. Oriental Orthodoxy continues today. Oriental Orthodoxy's institutional line runs back to the post-apostolic church. No body on this tree is the assembly of Acts 2; where a body claims that, the claim appears in the claimed-lineage layer.

Between the post-apostolic church and Oriental Orthodoxy stand 1 division along the institutional line, counting separations and disputed forks, not mergers, renewals or national organizations.

At a glance

Formed
Between 451 and 554, as a process rather than a single event
Family
Oriental Orthodox
Region
Egypt, Syria, Armenia, Ethiopia, India
Key figures
Dioscorus of Alexandria, Severus of Antioch, Jacob Baradaeus
Cause tags
Doctrine, Politics, Governance
Also known as
Non-Chalcedonian churches; Miaphysite churches

What it separated from

Bodies organized out of it or separated from it: Coptic Orthodox Church of Alexandria, Syriac Orthodox Church of Antioch, Armenian Apostolic Church.

On the tree

Oriental Orthodoxy and its institutional line back to the post-apostolic churchAD 33today100301424431451The post-apostolic church (The spine)The post-apostolicchurchThe spineArmenian Apostolic Church (Oriental Orthodox)Armenian ApostolicChurchOriental OrthodoxChurch of the East (Church of the East)Church of the EastChurch of the EastThe conciliar church (The spine)The conciliar churchThe spineThe Chalcedonian church (The spine)The Chalcedonian churchThe spineCoptic Orthodox Church of Alexandria (Oriental Orthodox)Coptic Orthodox Churchof AlexandriaOriental OrthodoxOriental Orthodoxy (Oriental Orthodox)Oriental OrthodoxyOriental OrthodoxSyriac Orthodox Church of Antioch (Oriental Orthodox)Syriac Orthodox Churchof AntiochOriental Orthodox

Solid lines are separations and unions; dashed lines are renewals that began inside a body; dotted gray lines are national organizations of one communion; a diamond marks a fork event where neither side is drawn as the one that left. Every line runs back to the post-apostolic church; no body descends from the assembly of Acts 2.

The event

Council of Chalcedon, 451

Fourth ecumenical council; defined Christ as one person in two natures. The churches of Alexandria, Syria, and Armenia did not receive the definition; mutual excommunications followed.

The other body from this event: The Chalcedonian church.

  • 1990: Eastern Orthodox–Oriental Orthodox agreed statements (Chambésy) treat the difference as largely terminological.

Sources

Research compiled July 2026. Page data built 2026-10-10.