<P> The first offensive action by AEF units serving under non-American command was 1,000 men (four companies from the 33d Division AEF), with the Australian Corps during the Battle of Hamel on 4 July 1918 . (Corporal Thomas A. Pope was awarded the Medal of Honor for this battle .) This battle took place under the overall command of the Australian Corps commander, Lt. Gen. Sir John Monash . The Allied force in this battle combined artillery, armor, infantry, and air support (Combined arms), which served as a blueprint for all subsequent Allied attacks, using "tanks". </P> <P> U.S. Army and Marine Corps troops played a key role in helping stop the German thrust towards Paris, during the Second Battle of the Marne in June 1918 (at the Battle of Château - Thierry (1918) and the Battle of Belleau Wood Wood). The first major and distinctly American offensive was the reduction of the Saint Mihiel salient during September 1918 . During the Battle of Saint - Mihiel, Pershing commanded the U.S. First Army, composed of seven divisions and more than 500,000 men, in the largest offensive operation ever undertaken by United States armed forces . This successful offensive was followed by the Meuse - Argonne offensive, lasting from September 26 to November 11, 1918, during which Pershing commanded more than one million American and French combatants . In these two military operations, Allied forces recovered more than 200 sq mi (488 km) of French territory from the German army . By the time the World War I Armistice had suspended all combat on November 11, 1918, the American Expeditionary Forces had evolved into a modern, combat - tested army . </P> <P> Late in the war, American units ultimately fought in two other theaters at the request of the European powers . Pershing sent troops of the 332d Infantry Regiment to Italy, and President Wilson agreed to send some troops, the 27th and 339th Infantry Regiments, to Russia . These latter two were known as the American Expeditionary Force Siberia, and the American Expeditionary Force North Russia . </P> <P> The AEF sustained about 320,000 casualties: 53,402 battle deaths, 63,114 noncombat deaths and 204,000 wounded . </P>

How did american entry into ww1 affect german strategy