American Expeditionary Forces

American Expeditionary Forces (AEF), name given to the U.S. forces serving in Europe during World War I. Its commander was General John Pershing. The first U.S. troops arrived in June 1917 and saw major action in May 1918, when they relieved the French at Château-Thierry and stopped a German advance. In June, some 6,000 U.S. marines were killed at Belleau Wood. U.S. forces were important in stemming the German counteroffensive in the second Battle of the Marne (July–Aug. 1918). By the end of the war the AEF held one-fourth of the line and had taken part in 13 battles, most of them major encounters. U.S. troops were at the front for a total of 200 days, with 1,993,000 men fighting at the end of the war. Over 100,000 members of the AEF were killed in action, a similar number died of disease (especially influenza), and more than 200,000 were wounded.

See also: Pershing, John Joseph; World War I.