As part of the Second Battle of the Marne, American forces under Gen. John Pershing teamed with the French to earn a key victory at Château-Thierry. The Allied forces executed a surprise early morning counterattack on the Germans, suffering major casualties but gaining important ground.
Allied forces under American Gen. John Pershing began the Saint-Mihiel offensive on September 12. The Allies successfully pushed the Germans out of the Saint-Mihiel salient in France, opening rail communications between Paris and portions of the eastern front and demoralizing German forces.
American forces took part in the forty-seven-day Meuse-Argonne offensive. The Allies advanced through the Argonne Forest and pushed the German line back until, cornered and with no hope for success, the Germans agreed to cease fire and an armistice on November 11.