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The Assyrian Church of the East / Assyrian Church of the East

Assyrian Church of the East

Number of faithfulapprox. 400,000
Title of First HierarchCatholicos-Patriarch of the Assyrian Church of the East
See of the First HierarchErbil (Iraq)
Current incumbentMar Awa III. (Royel), born 1975, in office since 2021
Bishops and dioceses15 bishops; 12 dioceses
RiteEast Syrian
Liturgical languageSyriac
Presence in Austriaapprox. 400 believers, 1 priest
Presence in Germanyapprox. 5,000 believers; 11 parishes, 4 priests

The Apostolic Assyrian Church of the East goes back to the early patriarchate of Seleucia-Ctesiphon, which developed into the administrative center of the East Syrian tradition from the 5th century onwards. Its spiritual focus was shaped by the theological schools of Edessa and Nusaybin. From an early stage, the centers of East Syrian Christianity were already located outside the borders of the Roman Empire. This meant that the East Syrian Church only accepted the decrees of the first two ecumenical councils of Nicaea in 325 and Constantinople in 381, while at the beginning of the 5th century, the decrees of the following ecumenical councils were not received at all.

From the 7th century onwards, the Assyrian Church of the East developed a very dynamic and efficient missionary work in the Far East, through which the sphere of influence of this church grew significantly across Central Asia and India to China. In the early Middle Ages, the East Syriac Church formed the world's largest Christian community. In the 13th and 14th centuries, the East Syriac church was also able to further consolidate its position in the Mongolian world-empire founded by Genghis Khan. The Khans of the Golden Horde valued the learning of the East Syrian Christians and entrusted them with important tasks in the administration of their great empire. The decline of the flourishing church life in Central Asia and China began during the second half of the 14th century, when the from 1368 ruling Ming dynasty in China withdrew their support to the East Syriac Church. In 1370, with the establishment of the empire of Timur-Leng, the East Syriac Christians were persecuted and murdered.

After the Ottoman conquest of large parts of the area of the East Syrian Church, at the beginning of the 16th century, the Assyrian Church increasingly lost its importance. From the 16th to the 19th century, the Assyrians led a secluded life in which family clans decided on the appointment of bishops while the Catholicos was at the same time the secular leader of this ethnic group. By the early 20th century, the number of faithful had dropped to approximately 150,000. During the First World War, the Assyrians fought on the side of the Russians and the British against the Turks and were driven out of their traditional settlement area. Only about a third of them were able to escape to the British-ruled region around Baghdad. In 1933 the patriarch was expelled from Iraq and, after stays in Cyprus and several European capitals, finally took up residence in the Assyrian diaspora community in Chicago (Illinois/USA) at the beginning of the 1940s.

From the USA, Patriarch Mar Eshai Shimun XXI. strived to rebuild his church. While his efforts in the diaspora were very successful managing also to re-establish unity with the metropolis in southern India in 1961, some reforms introduced by Patriarch Shimun in March 1964 led to a schism between the exiled Assyrians and those remaining in Iraq. The latter rejected the introduction of the Gregorian calendar and the shortening of Lent as “Western” innovations. This led to a split that gave rise to the ↗ Ancient Apostolic Church of the East.

Under Catholicos Patriarch Mar Dinkha IV (1976-2015), the Assyrian Church of the East increasingly opened itself up to ecumenical dialogue. Prepared by relevant conferences of the PRO ORIENTE Foundation in Vienna, Pope John Paul II and Mar Dinkha IV signed a joint Christological Declaration in 1994, with which the centuries-old Christological differences could be officially resolved. In the years that followed, representatives of the Assyrian and Catholic Churches met regularly for ecumenical discussions, which also led to a remarkable rapprochement between the Assyrian Church of the East and the ↗ Chaldean Church. Against this backdrop, in July 2001, the Vatican permitted limited Eucharistic communion between Assyrians and Chaldeans. Catholicos Patriarch Mar Gewargis III. (2015-2021) moved the seat of the Patriarchate back to Iraq, to the city of Erbil.


  • S. Lundgren, Die Assyrer. Von Ninive bis Gütersloh, Berlin 2015.
  • W. Hage, Die Apostolische Kirche des Ostens, in: ders., Das orientalische Christentum, Stuttgart 2007, 269-313.
  • Chr. Baumer, Frühes Christentum zwischen Euphrat und Jangtse. Eine Zeitreise entlang der Seidenstraße zur Kirche des Ostens, Stuttgart 2005.
  • W. Baum / D. W. Winkler, Die Apostolische Kirche des Ostens. Geschichte der sogenannten Nestorianer, Klagenfurt 2000.