The missionary Diocese of Lake Rukwa (DLR) was carved out of the Diocese of Western Tanganyika and was officially established as a diocese on 13thJune, 2010. It is located in the south western part of Tanzania in the geographical and political regions of Rukwa and Katavi. The Diocese covers three (3) Districts of Katavi region namely Mpanda, Nsimbo and Mlele districts and four (4) districts of Rukwa region namely Nkasi, Sumbawanga Rural, Sumbawanga Municipal and Kalambo districts. Important features in the diocese include the Katavi National Park, Lake Rukwa and Lake Tanganyika.
The population of the area covered by the diocese is estimated at 1.5m as of the 2012 census. The main ethnic groups include kinga, fipa, bende, konongo, pimbwe, ha, sukuma, ndali, and hutu who are mainly refugees from Burundi.