The Diocese of Hazaribagh was erected by Pope John Paul II, by bifurcating the Diocese of Daltonganj. The new diocese comprises the civil districts of Chatra, Hazaribag, Koderma and Bokaro excluding, however, the Chandankyari block of Bokaro district together with that portion of Chas block which lies to the east of National Highway 32.

The Catholic population of the diocese comprises scheduled tribes (Chiefly Oraons, Mundas, Santals and Kharias) Scheduled Castes and mixed groups of Catholics migrated from various parts of India.