It is named for the historical British North American territory of Rupert's Land, which was contained within the original diocesan boundaries.

The diocese is located in southern Manitoba and north-western Ontario, consisting of the area immediately surrounding Winnipeg, stretching north from the Canada–US border to near the top of Lake Winnipeg, and extending over the Ontario border to incorporate the parishes of the former southern region of the Diocese of Keewatin.

The area of the diocese was the cradle of European settlement in western Canada, and was thus the original locus of Anglican missionary activity there.

During the 19th and early 20th centuries, the diocese also played a key role in the missionary activity of the Anglican Church in western Canada, particularly in the prairie provinces and the Arctic.

[citation needed] The school was conservative and prided itself in pushing boys to their physical and psychological breaking points.