With much of Europe under Nazi control, the Russians face a daunting German invasion in June 1941; by December, the United States would be compelled to enter the war; examining if the Allies could unify their efforts.

The Tehran Conference of 1943 represents the greatest concentration of power the world has ever seen; there, allied forces finalize plans for Operation Overlord; by early 1945, the Allies meet in Yalta to discuss the future of the world.