town, centre of the Rainy River district, western Ontario, Canada. It lies on the north bank of Rainy River (the Canada–U.S. boundary), opposite International Falls, Minn. Originating as a fur-trading post, Fort-Saint-Pierre, built near the present townsite in 1731, it was renamed Fort Frances in 1830 in honour of the wife of Sir George Simpson, general superintendent of the Hudson's Bay Company. The town's early growth was aided by commercial fishing and logging operations, its position on a trade route, and a canal built in the late 1870s that circumvented falls at the outlet of adjacent Rainy Lake.

A busy point of entry and the centre of a popular hunting, fishing, and canoeing area, Fort Frances remains primarily a lumbering town. Milling operations in paper, pulp, and lumber utilize hydroelectric power, which is generated nearby. Inc. 1903. Pop. (2006) 8,103.