The Chaldean Syrian Church is an Indian Syriac Christian Church which is an archbishopric of the Assyrian Church of the East based in Iraq. Its members are a part of the St. Thomas Christian community, who trace their origins to the evangelical activity of Thomas the Apostle in the 1st century. They are almost exclusively based in the state of Kerala, with the church's Cathedral located in Thrissur. Despite carrying the "Chaldean" title in its name, the church is unrelated to the Chaldean Catholic Church of the Middle East, an Eastern Catholic church in communion with the Pope. The Chaldean Syrian church is the modern day continuation of the East Syriac Rite Assyrian Church of the East in India, after the majority of its followers converted to Catholicism or West Syriac Rite Churches. However, when a new patriarch was elected a few decades later named Mar Thoma I, the Coonan Cross Oath of 1653 was made stating that the Church of India would break off from the Catholic Church. This was largely because a request for reunification with the Church of the East in the Middle East was declined, resulting in a bishop who was to reunite the churches named Ahatallah being tortured and killed by the Portuguese in 1652. As a result, Thoma formed his own independent church and waited for a bishop from the Assyrian Church of the East to come and officially reunite them.
Chaldean syrian church, Trissur
Kurisupalli, High Rd, Thrissur, Kerala 680001