Winnipeg

From Turtledove

Winnipeg is the capital of Manitoba, Canada. Its fall to the United States in the Great War in 1917 signaled the end of Canada's participation in the war, and the end of its existance as an independent country.

In 1942, supported by the British, Canadian rebels expelled a Quebecois garrison from the city. The garrison had gone to Winnipeg to relieve US forces, allowing the US troops to be used in combat against the Confedeate States. US forces advanced on Winnipeg shortly thereafter.