Holy See of the East is an honorary name of the sees of a number of Christian churches in the Middle East and India.
The Head of Malankara Marthoma Syrian Church Malankara Orthodox Syrian Church and the head of the Syro-Malabar Catholic Church is commonly known as the successor to the Holy Apostolic See of St. Thomas.[1] The Seat of the Patriarchs of the Chaldean Catholic Church and the Nestorian Catholicos-Patriarchs which emerged from the Ancient Church of the East is also a part of the Holy See of the East.
Saint Thomas Christians after the Coonan Cross Oath who welcomed the Bishop Gregorios of the Syriac Orthodox Church in 1665 Church of Antioch claims the title of the Holy See of the East, since St. Thomas is the founder of this church. The Malankara Orthodox Syrian Church which evolved out of the Malankara Church as a part of the Oriental Orthodox Churches claims the title of the Catholicos of the East and the Holy Apostolic See of St. Thomas.[2] The Malankara Syrian Catholic Church which evolved from the Malankara Church as a part of the Eastern Catholic Church in full communion with the Holy See of Rome also claims the title of the Catholicos and the Holy Apostolic See of St. Thomas.[3]
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.
The current Patriarch of the Assyrian Church of the East is Mar Gewargis III, who took charge after the death of Mar Dinkha IV in 2015. The current Seat of the Catholicos-Patriarch of Assyrian Church of the East is in Chicago, Illinois, USA.
The official title of the major archeparch of the Syro-Malabar Church is the Metropolitan and Gate of All India. The church is headed by the Major Archbishop of Ernakulam-Angamaly, Cardinal Mar George Alencherry.
The current Seat of the Major Archiepiscopal Curia is in Mount St. Thomas near Kakkanad, Kerala, India.[4]
The Chaldean Catholic Church is a part of the Eastern Rite Churches under the patronage of Pope Francis of Rome and under the leadership of the Patriarch, Louis Raphael I Sako. The patriarchal see is Babil(Babylon).
The official title of the supreme head of the Malankara Orthodox Syrian Church also known as Indian Orthodox Church is the Catholicos of the East on the Apostolic Throne of St. Thomas. The present Catholicos is Baselios Marthoma Mathews III, who was enthroned on 15 October 2021 in Parumala, Kerala at St. Peter and St. Paul's Church, Parumala. The current seat of the Catholicos of the East is in Kottayam, Kerala, India.
The official title of the Head & Father of the Syro-Malankara Catholic Church is the successor to the Holy Apostolic See of St. Thomas in India. The church is headed by the Major Archbishop of Trivandrum, Baselios Cardinal Cleemis Catholicos.
The current Seat of the Major Archiepiscopal Curia is in Catholicate Centre, Trivandrum, Kerala, India.[5]
The official title of the Supreme head of the church is the Mar Thoma Metropolitan of the apostolic see of St. Thomas, The current primate is His Beatitude The Most Reverend Dr. Theodosius Mar Thoma. The seat of the Mar Thoma Metropolitan is in Poolatheen, Thiruvalla