By summer 1918, a million American soldiers, or "doughboys" as they were often called, of the American Expeditionary Force (AEF) were in Europe, serving on the Western Front under the command of General John Pershing, with 25,000 more arriving every week. The failure of the German Army's Spring Offensive exhausted its manpower reserves and they were unable to launch new offensives. The Imperial German Navy and home front then revolted and a new German government signed a conditional surrender, the Armistice, ending the war on the Western Front on 11 November 1918.