By October 1918, the U.S. had more than a million men fighting in the Meuse-Argonne campaign. The American Expeditionary Forces' logistics army, the Services of Supply (SOS), provided critical support to the combat forces. An enormous array of maintenance, medical, motor transport, railroad, quartermaster and engineer units served in this role--as well as British women from Queen Mary's Army Auxiliary Corps, African American labor and pioneer regiments, a U.S. Marine brigade led by a legendary officer, volunteers from the Salvation Army, Chinese laborers and even German prisoners of war.. The SOS kept American soldiers at the front supplied with "bullets, bandages and beans" while repairing weapons, producing vast quantities of lumber, buying horses from Spain, operating a massive railroad network, caring for the sick and wounded, fighting fires on troopships, driving trucks under enemy fire and administering a notorious prison. This book gives a full account of perhaps the most overlooked yet crucial military effort of World War I.