The Latin Diocese of Trivandrum has the territory consisiting of Trivandrum and Chirayinkil Taluks of Thiruvananthapuram District with a small strip of coastal belt from Kovalam to Pozhiyoor in Neyyattinkara Taluk and Neerody to Eramainthura of K. K. District in Tamilnadu.

Christianity in these parts dates from the time of the arrival of the Portuguese in India and perhaps earlier. It is very likely that the Franciscan and Dominican fathers of the middle ages who evangelized Quilon and its suburbs worked also in Trivandrum. Some of the Churches of this Diocese claim to be of pre-Portuguese origin.

With the arrival of the Portuguese but especially with the advent of the pioneer missionary, St. Francis Xavier, Christanity spread far and wide in these parts with the result that by the close of the sixteenth century there were well-established christian communities all along the coast. But unfortunately with the suppression of the Society of Jesus this missionary enterprise came to a close.

The second phase of the missionary enterprise in the Diocese begins with the dawn of the present century. The saintly Archbishop Benziger who became Co-adjutor Bishop of Quilon in 1900 and Bishop in 1905 was the apostle who propagated Christianity in the Diocese through the fragrance of his saintly life, wise leadership and unceasing assistance to his priests. In 1931 when he retired to the Carmel Hill monastery there were Christian communities established in almost all places of the interior region. As early as 1919, Abp Benziger recommended the establishment of the Latin Diocese of Trivandrum, but it materialized only after his retirement.

On July 1, 1937, by the Bull “ In Ora Malabarica” Pope Pius XI created the Latin Diocese of Trivandrum with the four taluks of Neyyattinkara, Nedumangad, Trivandrum and Chiryinkeezh bifurcated from the Diocese of Quilon .Bishop Vincent V. Dereere, OCD , Bishop of Quilon was transferred to the newly erected Latin Diocese of Trivandrum which was entrusted to the Carmelites of the Flanders Province (Belgium).

In 1952 when the Diocese of Alleppey was erected by the bifurcation of the Padroado Diocese of Cochin, the narrow strip of coastal parishes which formed the Trivandrum Portuguese Mission was temporarily annexed to the Latin Diocese of Trivandrum with with Bishop Vincent V. Dereere, ocd, as its administrator. On May 20, 1955 this territory was definitely integrated in the Latin Diocese of Trivandrum.

On October 24, 1966 when Bishop Vincent V. Dereere, ocd, resigned from the See of Trivandrum, Bishop Peter Bernard Pereira was the first Indian to be appointed Bishop of Trivandrum and the Diocese passed into the hands of the indigenous clergy.

On July 16, 1996, by the Bull “Ad aptius Provehendum” of Pope John Paul II the Diocese is bifurcated to form the new Diocese of Neyyattinkara.

The Diocese is bounded on the north by the Diocese of Quilon, on the East by the Diocese of Neyyatinkara, on the West by the Arabian Sea and on the South by the Diocese of Kottar.