The diocese is in the northwestern part of Orissa state in the eastern India. In a land area of 9,675 square kilometers lives a population of 1,829,412. The diocese has only one civil district: Sundergarh. Important cities are: Sundergarh and Rourkela. Sundergarh is the district headquarters.
Predominant people in the diocese are various tribals like Oraon, Kharia, Munda, Kisan etc.
The languages spoken are: Oriya, Sadri, Khadia, Munda, Kisan, Sundargadi Odia, Oraon, Hindi and English.
Rourkela diocese was created on July 4, 1979, by taking civil district of Sundargarh from the diocese of Sambalpur in the state of Orissa. Divine Word Bishop Alphonse Bilung was appointed its first bishop. Divine Word Bishop Raphael Cheenath of Sambalpur, who stayed in Rourkela, moved his residence to Sambalpur, after the bifurcation.
The seeds of faith had been sown in the region by the Belgian Jesuit missioners from the neighbouring Ranchi diocese. People credit their faith to the famous Belgian Jesuit Missioner of Chhotanagpur (Ranchi) Father Constant Lievens. In 2008 the diocese celebrated the first centenary of the arrival of Catholic faith in the region.
Gangpur is the first mission where the Belgian Jesuit missioners from Ranchi started. So the region was then known as Gangpur mission. Today it has given birth to two dioceses: Rourkela and Sambalpur.
Kesramal is the first parish opened by them in 1908. It has today a Catholic population of about 15,000.
Though the Belgian Jesuit missioners sowed the seeds of faith here, in 1948 the region was entrusted to the Divine Word (SVD) missioners.
The Catholics are mostly the tribals belonging to the Oraon, Munda, Kharia and Kissan communities. The Kissans are the latest converts. Besides evangelization, the missioners focus on the faith-formation, education and social development of the Catholics and others. The diocese gives also great importance to Small Christian Communities (SCC)
There are four deaneries: Rourkela, Rajgangpur, Birmitrapur, and Sundergarh.
People's main occupation is agriculture. Mostly they cultivate paddy. Rich minerals are found here, especially high quality iron ore. The famous Rourkela Steel is situated here. Industrialization, like the Steel Plant, has made rapid progress in the recent years in the area.
Regional Engineering College (National Institute of Technology) at Rourkela is a prestigious educational centre in the state.