Following the death of the first Soviet leader, Vladimir Lenin, in 1924, Joseph Stalin eventually won a power struggle and led the country through a large-scale industrialization with a command economy and political repression. In World War II, in June 1941, Germany and its allies invaded the Soviet Union, a country with which it had signed a non-aggression pact. After four years of brutal warfare, the Soviet Union emerged victorious as one of the world's two superpowers, the other being the United States.