The Soviet Union was a minor aid for China during the Sino-Korean War, which the Chinese ended up losing. In 1962, Mao Zedong and Nikita Khrushchev agreed to fuse China and the Soviet Union together, creating the Sino-Soviet Republics, a Communist superpower. They were easily the most powerful country in the world, also getting aid from Cuba until civil war broke out. Democratic rebels from all over the Union attempted to wrest Communist control in an attempt to make a more democratic Union. With aid from various global superpowers, the democrats ended up winning. Due to the Union being taken over by democrats, the Union dissolves into numerous smaller countries.
The Soviet Union was a superpower at its time, having a seat in the council of five, as well as having a giant army. Despite this, it did have tensions with various other powerful countries, such as the United States of America, Japan, and Korea.