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American Expeditionary Forces


AMERICAN EXPEDITIONARY FORCES, the American troops serving in Europe during World War I. When the United States declared war on Germany following President Woodrow Wilson's ringing address to Congress, the country found itself without plans for organizing a force that would be capable of offensive action in modern warfare. On 26 May 1917, Major General John J. Pershing, whom Wilson had selected to command American land forces abroad, received orders to proceed with his staff to France. Shortly after his arrival, convinced that military assistance on a vast scale would be necessary to Allied success, Pershing cabled the War Department that it should consider sending at least one million men to France by the following May and that war plans should be based on a force ultimately amounting to three million. By the time of the armistice in November 1918, approximately two million men had been transported to Europe, where they took a decisive part in bringing the war to a successful conclusion. To do this, the United States had to create its own supply system to train, equip, and provide for the subsistence of a large and rapidly mobilized army.

In the spring and early summer of 1918, a series of powerful German offensives threatened to defeat the Allies. In the crisis, Pershing placed the entire resources of the American Expeditionary Forces at the disposal of the Allied High Command, postponing until 24 July 1918 the formation of the American First Army.

The assistance that the United States gave the Allies in combat began in May with the capture of Cantigny by an American division in the first independent American offensive operation of the war. This was followed early in June by the entrance into battle of two divisions that stopped the German advance on Paris near Château-Thierry. In July, two American divisions, with one Moroccan division, formed the spearhead of the counterattack against the Château-Thierry salient, which marked the turning point of the war. Approximately 300,000 American troops fought in this second Battle of the Marne. In mid-September, the American First Army of 550,000 men reduced the Saint-Mihiel salient. The Meuse-Argonne Offensive began in the latter part of September. After forty-seven days of intense fighting, this great battle ended brilliantly for the First and Second Armies, with the signing of the armistice on 11 November 1918. More than 1,200,000 American soldiers had participated.

With the cessation of hostilities, Congress and the American public immediately turned their attention to repatriating the troops. By the end of August 1919, the last American division had embarked for home, leaving only a small force in occupied Germany, and on 1 September 1919, Pershing and his staff sailed for the United States.


Hallas, James H. Doughboy War: The American Expeditionary Force in World War I. Boulder, Colo.: Lynne Rienner Publishers, 2000.

John J. Pershing / c. w.

See also Armistice of November 1918 ; Demobilization ; Mobilization .

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