The diocese's land area of 44,215 square kilometers covers the civil districts of Belgaum, Bagalkot, Dharwad, Gadag and Haveri in Karnataka State, and Chandgad Taluka of Kolhapur District in Maharashtra State.
Belgaum is one of the oldest, most prominent and culturally historical places in the Western Ghats, one of India's three main watersheds. It lies in a zone of cultural transition from Karnataka, Maharashtra and Goa, with an easily traceable history back to the second century A.D. The nearest major cities to Belgaum are Panaji in Goa, Hubli and Dharwad in Karnataka, and Kohlapur in Maharashtra. Many Catholics in the city of Belgaum trace their descent back to Goa.
Konkani, Kannada, Marathi, English and Tamil are in use.
The Diocese of Belgaum was erected on Sept. 19, 1953, with territory taken from the Archdiocese of Goa and the Diocese of Poona. At the same time, Father Michael Rodrigues of Poona Diocese was appointed the first Bishop of Belgaum.
North Kanara District was separated from Belgaum to form Karwar Diocese on Jan. 24, 1976.
- Patroness of the diocese: Our Lady of the Family Rosary of Fatima