The Russian Revolution took place in 1917, 1 year before the end of World war I, by the Bolsheviks. After the revolution, the Bolsheviks got out winner, and became the ones ruling Russia. The first decision they took was to retreat from the World War I, since it caused many casualties, economic problems, poverty, etc...,pulled out their soldiers from the battles, And signed a treaty with the Central Powers (Germany, the Ottomans, Bulgaria, and Austria-Hungary), which gave the central powers more troops to fight with, since Russia wasn't involved in the war anymore, and their troops in Russia were sent to reinforce other battles. The Allies needed now more troops to fight the Central powers, which was assisted by the United States.
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