Eastern Catholic Churches

The Eastern Catholic Churches (historically known by the now non-complimentary term Uniate Churches, which is still in use in some areas, and also by the inaccurate term eastern-rite Churches) are autonomous, self-governing (in Latin, sui iuris) particular churches in full communion with the Bishop of Rome, the Pope. Together with the Latin Church, they compose the worldwide Catholic Church. They preserve many centuries-old eastern liturgical, devotional, and theological traditions, shared in most cases with the various other Eastern Christian churches with which they were once associated. A few have never been out of communion with the Pope, a claim made, for instance, by the Maronites. Although the Churches with which most were formerly associated may be of traditions out of communion with each other (Eastern Orthodox Church, Oriental Orthodoxy, Church of the East), Eastern Catholic Churches of whatever tradition are all in communion with one another and with the Latin or Western Church. However, they vary in theological emphasis, forms of liturgical worship and popular piety, canonical discipline and terminology. They all recognize the central role of the Bishop of Rome within the College of Bishops and his infallibility when speaking ex cathedra. As a number of theological issues separate them from their counterparts who are of similar traditions, but who are out of communion with Rome, they do not admit members of such other churches to the Eucharist or the other sacraments except in the circumstances indicated in canon law. In the case of the Eastern Orthodox Churches, these issues result primarily, though not exclusively, from differences in the understanding of the role and the extent of the authority of the Bishop of Rome.

Historically, Eastern Catholic Churches were located in Eastern Europe, the Asian Middle East, Northern Africa, and India. Due to migration they are now also in Western Europe, the Americas and Oceania, where eparchies have been established alongside the Latin dioceses. Eritrea has only an Eastern Catholic hierarchy, with no Latin structure.

The terms Byzantine Catholic and Greek Catholic are used of those who belong to Churches that use the Byzantine Rite. The terms Oriental Catholic and Eastern Catholic include these, but are broader, since they also cover Catholics who follow the Alexandrian, Antiochian, Armenian and Chaldean liturgical traditions.