American Expeditionary Force Siberia

The American Expeditionary Force Siberia (AEF Siberia) was a United States Army force that was involved in the Russian Civil War in Vladivostok, Russian Empire, during the end of World War I after the October Revolution, from 1918 to 1920. As a result of this expedition, which failed but became known to the Bolsheviks, early relations between the United States and the Soviet Union would be low.

U.S. President Woodrow Wilson's claimed objectives for sending troops to Siberia were as much diplomatic as they were military. One major reason was to rescue the 40,000 men of the Czechoslovak Legion, who were being held up by Bolshevik forces as they attempted to make their way along the Trans-Siberian Railroad to Vladivostok, and it was hoped, eventually to the Western Front. Another major reason was to protect the large quantities of military supplies and railroad rolling stock that the United States had sent to the Russian Far East in support of the prior Russian government's war efforts on the Eastern Front. Equally stressed by Wilson was the need to "steady any efforts at self-government or self defense in which the Russians themselves may be willing to accept assistance." At the time, Bolshevik forces controlled only small pockets in Siberia and President Wilson wanted to make sure that neither Cossack marauders nor the Japanese military would take advantage of the unstable political environment along the strategic railroad line and in the resource-rich Siberian regions that straddled it.

Concurrently and for similar reasons, about 5,000 American soldiers were sent to Arkhangelsk (Archangel), Russia by Wilson as part of the separate Polar Bear Expedition.

The American Expeditionary Force Siberia was commanded by Major General William S. Graves and eventually totaled 7,950 officers and enlisted men. The AEF Siberia included the U.S. Army's 27th and 31st Infantry Regiments, plus large numbers of volunteers from the 12th Infantry Regiments, 13th, and 62nd Infantry Regiments of the 8th Division, Graves' former division command.

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