The history of Christianity in Vasai region is almost as old as that of the Church in India. While St. Thomas the Apostle is known to have set foot in the Malabar Coast, tradition claims that yet another apostle St. Bartholomew came to the neighborhood of Vasai and preached the Gospel in the vicinity of Kalyan. A reference to ‘India Felix’ and the Christian community of Kalyan ‘foundation town’ is found in the Council of Nicea held in 325 AD. Kalyan, a taluka near Vasai, had a Bishop appointed from Persia, in the 6th century itself. Historical records are available regarding the existence of a church dedicated to St. Thomas at Sopara, which is close to the present Bishop's House at Vasai.
Christianity blossomed in Vasai during the Portuguese period. The Portuguese entered Vasai along with their religious headquarters. Four Missionary Congregations-Franciscans, Jesuits, Dominicans and Augustinians were actively involved in the evangelisation work around Vasai Fort. Evangelization was at its peak in this region mainly during the second half of the 16th and the first half of the 17th centuries. In 1739 A.D., the Marathas conquered Vasai and drove away the Portuguese rulers along with the Missionaries. However, the Christians were permitted to practise their faith by having just a few priests from Goa. In 1665, the Island of Bombay passed into the hands of the British. During the new rule, the educational, cultural and social activities did not flourish in Vasai region, predominantly populated by the followers of Catholicism.
Vasai was under the Archdiocese of Goa between 1535-1886 and later under the Archdiocese of Damaun between 1886-1928 and finally came under the Archdiocese of Bombay in 1928. The new Diocese of Vasai was created out of Archdiocese of Bombay by Pope John Paul II on May 22, 1998. The Church of Our Lady of Grace was elevated to the status of a Cathedral and Most Rev Dr. Thomas Dabre the auxiliary Bishop of Bombay ever since1988 was nominated as its first Bishop The Episcopal installation of Most Rev Thomas Dabre as its first Bishop took place on August 15, 1998. St. Gonsalo Garcia, the Parton of Vasai, the only Canonized Martyr of India, hails from the Diocese. Following to the transfer of Bishop Thomas Dabre to the Diocese of Pune on April 4, 2008, Most Rev. Felix Anthony Machado was transferred from Nashik Diocese to the Diocese of Vasai on November 10, 2009 and was installed on December 19, 2009.
Former Prelates: Most Rev. Thomas Dabre (1998-2008)