Christianity in Kerala has supposedly existed since the 1st century A.D. It is said that St.Thomas, Apostle of Christ, came to Kodungalloor, a village port in Kerala, in 52 A.D. He began by converting four high-caste Brahmin families (thus called Nalillakkar), and soon a substantial number of people were converted to Christianity. St.Thomas himself is believed to have soon left for China and, on his way back to Mylapore, near Madras, was killed and buried there. The descendants of the converts from St.Thomas's time call themselves the Thomas Christians.

The Thomas Christians built their places of worship and supposedly settled down as a respected community living in harmony with the Hindus. The Kings of Travancore are said to have given them great honour and freedom. Certain copper plates to this effect are in the possession of the Thomas Christians.

For these reasons, the churches that they built are very much like the Hindu temples of the region. In most cases, at a casual At first glance, the only strict differences one would notice are the use of the cross and, on closer inspection, Christian motifs on the sculpted walls of the interior.

The liturgical rites of the Thomas Christians were always East Syrian. In the 4th century, one Thomas of Cana came to Kodungalloor with about three to four hundred Palestinian families. This resulted in a schism between the Syrians and the native Christians, creating Southerners and Northerners, respectively. The Roman influence began to creep in around the 13th century. Marco Polo was the first Roman to appear in Malabar. But he was in the service of Kublai Khan, who was an anti-Roman Venetian and had no ambitions for religious work.