Charles, You've asked about a fascinating and little known (or poorly remembered) chapter in US and US Army history. Stuart has given you the basic context. The Univ of Michigan has a web site about their collection on "the Polar Bear Expedition" (http://www.umich.edu/~bhl/bhl/mhchome/polarb.htm)
from which you'll see that the 85th Div, augmented by 339th Infantry, 310 Eng Bn, 337 Field Hospital, 337 Ambulance Co were sent to retain the Eastern Front, pressing on Germany, but became involved in fighting the Reds.
For the Far East component, the CO, MG William S. Graves, left a memoir, "America's Siberian Expedition" (NY, 1931), recounting how div from the States plus troops (31st Inf) from PI converged on Vlad as part of international coalition with Japanese and other allies(!). Graves was a straight-shooter, who tried to maintain impartiality, to the distress of a muddled political scene and allies who wanted to weigh in on one side (or the other). One side-aspect was trying to transport Czech troops (who had gotten stranded on the east side of the war lines by the Russian revolution) by water back to the Western Front to resume participation in the war. Graves' men were much involved in keeping the Trans-Siberian Railroad operating.
Some of the units retained reminders of their Russian service in unit insignia. And, as Stuart noted, the Archangel contingent were issued Russian small arms.
I recommend Graves' book (Interlibrary loan?), a VCR of "Dr. Zhivago," and a pot of good (well-laced?) tea on a wintry day to delve further into this subject. Thanks for raising it and stirring the memories.
PS (I believe we have a Company plate on the uniforms of the Northern contingent, perhaps 37th Infantry?)
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