Patriarch of the Church of the East

The Patriarch of the Church of the East (Patriarch of Babylon or Patriarch of the East) is the patriarch, or leader and head bishop (sometimes referred to as Catholicos or universal leader) of the Assyrian Church of the East. The position dates to the early centuries of Christianity within the Sassanid Empire, and the church has been known by a variety of names, including the Church of the East, Nestorian Church, the Persian Church, the Sassanid Church, or East Syrian. In the 16th and 17th century the Church, by now restricted to its original Assyrian homeland in Upper Mesopotamia, experienced a series of splits, resulting in a series of competing patriarchs and lineages. Today, the three principal churches that emerged from these splits, the Assyrian Church of the East, Ancient Church of the East and the Chaldean Catholic Church, each have their own patriarch, the Patriarch of the Assyrian Church of the East, the Patriarch of the Ancient Church of the East and the Patriarch of Babylon of the Chaldeans, respectively.

The geographic location of the patriarchate was first in the Persian capital of Seleucia-Ctesiphon in central Mesopotamia. In the 9th century the patriarchate moved to Baghdad and then through various cities in what was then Assyria (Assuristan/Athura) and is now northern Iraq, south east Turkey and northwest Iran, including, Tabriz, Mosul, and Maragheh on Lake Urmia. Following the Chaldean Catholic Church split from the Assyrian Church, the respective patriarchs of these churches continued to move around northern Iraq. In the 19th century, the patriarchate of the Assyrian Church of the East was in the village of Qudshanis in southeastern Turkey. In the 20th century, the Assyrian patriarch went into exile, relocating to Chicago, Illinois, United States. Another patriarchate, which split off in the 1960s as the Ancient Church of the East, is in Baghdad.

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