World War II included a military campaign.
The Axis powers ( Achsenmächte , 枢軸国 Sūjikukoku , Potenze dell ` Asse ) , also known as the Rome -- Berlin -- Tokyo Axis , were the nations that fought in World War II against the Allied Powers . World War II . It involved the vast majority of the world 's countries -- including all of the great powers -- eventually forming two opposing military alliances : the Allies and the Axis . Supplied by the Soviet Union , from late 1939 to early 1941 , in a series of campaigns and treaties , Germany conquered or controlled much of continental Europe , and formed the Axis alliance with Italy and Japan . The war continued primarily between the European Axis powers and the coalition of the United Kingdom and the British Commonwealth , with campaigns including the North Africa and East Africa campaigns , the aerial Battle of Britain , the Blitz bombing campaign , the Balkan Campaign as well as the long-running Battle of the Atlantic .