The Siberian Intervention (1918–1920) was a multinational military operation during the Russian Civil War in which Allied powers, including the United States, deployed forces to eastern Russia following the Bolshevik Revolution. Officially intended to protect military supplies, assist the Czechoslovak Legion, and stabilize the region, the intervention became entangled in the broader conflict between Red and anti-Bolshevik White forces. American troops, primarily from the American Expeditionary Force, Siberia, conducted guard and support operations along the Trans-Siberian Railway but avoided deep involvement in Russian internal politics. The mission concluded without achieving lasting strategic objectives and marked a complex episode of early U.S. engagement in post–World War I global affairs.