Union of Soviet Socialist Republics (Soviet Manchuria)

The Union of Soviet Socialist Republics (USSR), more commonly known as the Soviet Union is a constitutionally socialist state that has existed in Eurasia since 1922. Nominally a union of multiple subnational Soviet republics, its government and economy are highly centralized in a state that is unitary in most respects. The country is a one-party federation, governed by the Communist Party with Moscow as its capital.

The Soviet Union had its roots in the October Revolution of 1917, when the Bolsheviks, led by Vladimir Lenin, overthrew the Russian Provisional Government which had replaced Tsar Nicholas II. In 1922, the Soviet Union was formed with the unification of the Russian, Transcaucasian, Ukrainian, and Byelorussian republics. Following the death of Vladimir Lenin in 1924, the government underwent a leadership struggle with Joseph Stalin eventually coming to power in the mid-1920s. Stalin initiated several sweeping reforms, leading to rapid industrialization and collectivization. Political paranoia surrounded Stalin, leading to the Great Purge, which led to the removal of several of Stalin's opponents.

Shortly before World War II, Stalin signed the Molotov–Ribbentrop Pact agreeing to non-aggression with Nazi Germany, after which the two countries invaded Poland in September 1939. In June 1941, Germany invaded the Soviet Union￼, opening the largest and bloodiest theater of war in history. Soviet war casualties accounted for the highest proportion of the conflict in the effort of acquiring the upper hand over Axis forces at intense battles such as Stalingrad. Most of the territories overtaken by the Red Army either became satellite states or were incorporated into the Union. By 1947, the Cold War emerged as the Eastern Bloc united under the Warsaw Pact confronted NATO.

As a result of this, the Soviet Union and the United States engaged in several proxy wars in Africa, Asia and the Middle East. Most notably in Manchuria (1947-1948), Korea (1950-1954), Vietnam (1955-1967), Indonesia (1960-1964) and South America (1973-1976).

Following Stalin's death in 1953, a period of political and economic liberalization, known as "de-Stalinization" and "Khrushchev's Thaw", occurred under the leadership of Nikita Khrushchev. The Soviet Union took an early lead in the Space Race, with the first ever satellite and the first human spaceflight. In the 1970s, there was a brief détente of relations with the United States, but tensions resumed with the Soviet–Afghan War in 1979.