Obviously it's supposed to be France and Britain beating Nazi Germany in 1941, but there's something about the original misprint that appeals to me.
How did the world end up with two Frances, where is the second one, why are France and Britain fighting it.
Now I am presuming that the France that Britain is allied with is Western or Atlantic France, somewhat similar to OTL France is size and position, and the enemy France is Eastern or Germanic France, which as the name suggests is further east towards Central Europe.
So the first thing here is build a larger France and a quick look at Wikipedia shows that could be possible.