Catholic Eastern Churches

Catholic Eastern Churches and their Orthodox Counterparts

UPDATED:  There are now  twenty-three eastern churches in communion with Rome as of 2015 with the acceptance of the Eritrean Church into communion.  The official announcement from the Vatican.

These vary in size from quite large with multiple bishops and a patriarchate to quite small without any episcopal leadership at all.  All but two have direct counterparts in the Orthodox communions that are parallel in liturgy and discipline.

This table attempts to organize the relationship of these many independent churches to each other and their traditional roots.  The first column “Eastern Communion” denotes the three major sub-divisions of Orthodox communions.  These are the direct result of how various early churches accepted the first seven ecumenical councils that helped define and shape christianity.

The Assyrian Church of the East left the conciliar fold first by rejecting the third ecumenical council of Ephesus.  This council rejected the teachings of Nestorianism and bestowed the title Theotokos (god bearer) on Mary the mother of god.
The Oriental Orthodox Church rejected the fourth ecumenical council of Chalcedon.  This council rejected the teaching of monophysitism and defined the two natures of Christ as human and divine.

The Byzantine Church is also known as simply the Orthodox Church.  This includes all those who followed the liturgy and traditions that centered on the great church in Byzantinum (Constantinople, now Istanbul).  This is the main body of Orthodox christians and accept all seven of the early ecumenical councils.

As you can see, until modern times these communions are organized by simple geography.  But in the modern age with migration and colonization there is now significant communities that overlap in the same countries.  This is especially true in western europe, the Australian continent and the Americas.

You will also notice that three of these catholic eastern communities have long interruptions in there union relationship with Rome.  These occur when internal conflicts and regional politics prevented the continuation of the union for an extended period of time.

The Ukrainian communities also have a recent history of jurisdictional conflict on the Orthodox side.  There are currently three competing hierarchies claiming jurisdiction as the Orthodox church in Ukraine.

Also in eastern europe the Ruthenian catholic union has spawned additional national catholic eastern churches in Slovakia and Hungary.  And the traditional homeland in the Carpathian mountains of the Ruthenian church encompasses parts of Poland, Slovakia and Ukraine.  This is also a source of difficulty in the establishment of church discipline in the post communist age.

Hungary in particular makes for a difficulty in this chart.  The Hungarian eastern catholic community is culturally and liturgically related to the Ruthenian community.  But the very recent inroads of Orthodoxy into the traditionally Roman Catholic Hungary are from the Serbian Orthodox communities.  Here we have a unique situation where the Orthodox and catholic counterparts are from similar but not the same traditions.

For more information about any of these Orthodox or catholic communities see Roberson’s fine brief outlines in The Eastern Christian Churches: a brief Survey.

Catholic Eastern Churches Chart


Roberson, Ronald G. The Eastern Christian Churches : a brief survey. 7th ed. Roma: Orientalia Christiana, 2007.

Originally Posted May 01, 2010
Last Revised on December 21, 2016