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. Time of Russian civil war was notorious for various overprints on all kinds of issued stamps. Around 25 stamps of each issue were privately made in typography with only 2 inverted overprints made.
Please study the scans carefully. I do not post to P. Box, Croatia, Serbia, Slovenia, Bosnia, Montenegro, Macedonia (all of the Balkans), Eastern European countries. The item "Inverted, American Expeditionary Force Siberia, Air Mail, Rare, MNH, On 15k Blue" is in sale since Friday, April 19, 2019. This item is in the category "Stamps\United States\1901-1940 Unused".
The seller is "vvtesla" and is located in Zagreb, default. This item can be shipped worldwide.