Holy See of the East

The Seat of Nestorian Catholicos-Patriarchs and Indian Orthodox Catholicos of the East is commonly known as the Holy See of the East and the Holy See of St. Thomas, as the post of Catholicos of the East is the successor of St. Thomas.

Nestorian Churches of the East

Ancient Church of the East

His Holiness the Patriarch Mar Addai II, is the Catholicos of the Ancient Church of the East.

The current Seat of the Catholicos of Ancient Church of the East is in Baghdad, Iraq.

Assyrian Church of the East

Mar Dinkha IV is the current Catholicos-Patriarch of the Assyrian Church of the East.

The current Seat of the Catholicos of Assyrian Church of the East is in Chicago, Illinois, USA.

Oriental Orthodox Church of the East

Indian Orthodox Church

The official title of the supreme head of the The Indian Orthodox Church is "the Catholicos of the East on the Apostolic Throne of St. Thomas". The present is H.H. Mar Baselios Mar Thoma Didymos I, who was enthroned on October 31, 2005. The Indian Orthodox Church (also known as the Malankara Orthodox Church, Orthodox Church of the East, Malankara Orthodox Syrian Church, Orthodox Syrian Church of the East) is a prominent member of the Oriental Orthodox Church family .

The current Seat of the Indian Orthodox Catholicos of the East is in Kottayam, Kerala, India.

Holy See of Antioch

Few Christian denominations can claim the antiquity of the Syriac Orthodox Church of Antioch, whose foundations can be traced back to the very dawn of Christianity. The Church justifiably prides itself as being one of the earliest established apostolic churches. It was in Antioch, after all, that the followers of Jesus were called Christians as we are told in the New Testament, "The disciples were first called Christians in Antioch." (Acts 11:26).

According to ecclesiastical tradition, the Church of Antioch is the second established church in Christendom after Jerusalem, and the prominence of its Apostolic See is well documented. In his Chronicon (I, 2), the church historian Eusebius of Caesarea tells us that Apostle St. Peter established a bishopric in Antioch and became its first bishop. He also tells us that St. Peter was succeeded by Evodius. In another historical work, Historia Ecclesiastica, Eusebius tells us that Ignatius the Illuminator, "a name of note to most men, [was] the second after Peter to the bishopric of Antioch" (III, 36).

In the mid 5th century, the Bishop of Antioch, and his counterparts in Alexandria, Byzantium and Rome, would be called patriarchs. The Syriac Orthodox Patriarch of Antioch used to be known by his own name; however, since 1293 the patriarchs of Antioch adopted the name Ignatius, after the Illuminator. The See of Antioch continues to flourish till our day, with His Holiness Patriarch Ignatius Zakka I, being the 122nd in the line of legitimate patriarchs.