Allied intervention in the Russian Civil War
The Russian Civil War happened in the early 1900s. It was a fight between the Red Army (who wanted a more socialist society) and the White Army (who wanted to keep the old ruling class). It was a scary time, and lots of people were hurt or killed during it. After a while, countries like Britain, France, Japan, and the United States decided to help the White Army and sent soldiers and supplies to help stop the Red Army. This is called Allied Intervention and it helped the White Army win the Civil War.
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