In February 1917, Tsar (King) Nicholas II of the Russian Empire was overthrown because people were unhappy with their living conditions, especially during World War I. The new government in Russia was a democratic socialist government. Unfortunately, it was ineffective, and people were still unhappy. In November 1917, a communist group called the Bolsheviks led by Vladimir Lenin overthrew the new government. They were supported by groups of workers called Soviets. The Bolsheviks created a new communist government called the Russian Soviet Federative Socialist Republic (called simply Soviet Russia or the Russian SFSR).
However, not everyone supported the communists. Many countries that had been a part of the Russian Empire had left, such as Latvia, Lithuania, Estonia, Poland, and Finland. The Russian Civil War began, with the Russian SFSR's "Red Army" fighting against the "White Army", the group of all Russians against the communists. The White Army was not very united or organized. The Allied Powers of World War I, such as the United States, United Kingdom, and France, invaded Russia to support the White Army.

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