Rooted in the ancient Christian tradition of Kalyan, the Diocese of Bombay serves Mumbai, Konkan and adjoining regions of western India, together with Qatar and Bahrain.
Tradition holds that St. Thomas landed at Kalyan, the ancient seaport near Mumbai, before reaching Kerala, and historical records indicate that until the Muslim invasions a sizeable congregation and a bishop existed there, using the Gospel of St. Matthew. On this basis there were proposals to name the diocese after Kalyan. The prominence of Bombay, however, overshadowed these proposals, and the Syro-Malabar Catholics subsequently adopted the name Eparchy of Kalyan for their own diocese.
The Diocese of Bombay was established with the 1976 division of the outside-Kerala diocese. H.G. Geevarghese Mar Coorilos, the present Metropolitan, assisted Mar Theophilus as Assistant Metropolitan from 1991 to 1997 before assuming charge of the diocese, which then extended across Maharashtra, Gujarat, Goa, a portion of Karnataka, Bahrain, Qatar, Abu Dhabi and Saudi Arabia. The diocese benefited during this period from the tenure of P.C. Alexander, a Malankara Orthodox Christian, as Governor of Maharashtra from 1993 to 2002.
A further reorganisation of the outside-Kerala dioceses in 2012 reduced its jurisdiction to Mumbai, Konkan, the Maratha region and parts of Vidarbha in Maharashtra, Southern Gujarat, Northern Karnataka, and the overseas territories of Qatar and Bahrain.
9 districts, listed alphabetically.