World War II Europe
In December 1941, Axis forces controlled virtually all of Europe as well as northern Africa. The Soviet Union was on the brink of collapse, and Britain was the sole Allied power in the West.
The Allies adopted a Europe-first strategy. To liberate France, the Allies needed to weaken Germany by bombing and blockade and then open a second front in Europe. This would relieve pressure on the Soviet Army. In 1942 and 1943, the Allies conducted a series of invasions in North Africa and Italy to occupy German forces while building up the necessary troops, ships, and equipment for an invasion of France.