Science played a large role, with advances in sonar(for detection of submarines), computers(to decrypt enemy codes), and of course the invention and deployment of the nuclear bomb(nuclear energy). Another great application of science was Radar (Radio Detection And Ranging) Great Britan used radar very successfully in repelling the German air campaign over Britans' airspace. (See "The battle of Britan")
The role of what?
Lenin had no role in World War 2. He had died in 1924 about 15 years before World War 2 started.
the allies role in world war 2 was to liberate Europe & the pacific against the axis the axis role in world war 2 was to take over the world & execute Jews
Sweden played a very small role in World War 1 and World War 2. They were a neutral nation. In World War 2 they did help 700 Jews escape from the Nazis in Denmark.
i have no idea.
Nazi Germany started World War 2 in Europe.
World War 1 World War 2 Korean War
Mario!=D and his role of world war 2
It brought the US into the war
None. UN was created after World War 2.