You may know that the Apostle Thomas reached India, and possibly died there, in his missionary endeavours.
Whatever the truth is, we can certainly find a thriving Orthodox church on the Malabar coast (South-Vest of India, Kerala State).
This Oriental (non-Chalcedonian) rite church is called The Malankara Orthodox Syrian Church (see their website HERE). This church, according to Fr. Roberson (see HERE) has about 1.2mln members. This Indian church, like many others, went through a series of splits. Here is an image of the present situation, in historical perspective:
In 1836 a reformation movement was started in this church, that led to the creation of Mar Thoma Syrian Church of Malabar.According to Fr. Boberson, the church has about 700,000 members and is in communion with Anglican provinces.
I have a special interest in this subject, because two of my World Vision colleagues are from this church. Dr. Saphir Athyal, a Princeton graduate and a WV veteran, was in charge of my sector in Asia when I joined WV. He was followed by Dr. CC Mathews, who is now a bishop of this church, under the name, Mathews Mar Makarios Episcopa (see HERE the announcement of his enthronisation). Their church has just celebrated its 175th anniversary, as we find out in an article published by Ecumenical News International (ENI). Here are a fee quotes from this informative text:
The Mar Thoma church traces its faith to St. Thomas the Apostle who is said to have reached Kerala in A.D. 52 with spice merchants from the Middle East and died a martyr in 72 A.D. at Mylapore.
The church treats August 16, 1836 as its “reformation” day and later assumed the name Mar Thoma (church of St. Thomas) after breaking away from the Orthodox fold under the influence of Anglican theology.
On his first visit to Kerala, where Christians account for one-fifth of the state’s 33 million people, Tveit hailed the Mar Thoma church’s “blending of two characteristic traits of the eastern ecclesial tradition and ethos as well as your reformation ideals corresponding to … reformation movements in the Western Church.”