U.S. Army recruiting for WWI at an entrance to Central Park, New York City, NY. The American Expeditionary Forces (AEF) were the United States Armed Forces sent to Europe in World War I. During the United States campaigns in World War I the AEF fought in France alongside French and British allied forces in the last year of the war, against Imperial German forces. The AEF helped the French Army on the Western Front during the Aisne Offensive in June 1918, and fought its major actions in the Saint-Mihiel and Meuse-Argonne Offensives in late 1918. The AEF sustained about 320,000 casualties; 53,402 battle deaths, 63,114 non combat deaths and 204,000 wounded. The influenza pandemic during the fall of 1918 took the lives of more than 25,000 men from the AEF while another 360,000 became gravely ill. Undated, uncredited.