In 1889, Dalton changed his name to Albert Clayton Dalton and enlisted in the U.S. army as a member of Company A, 22nd Infantry Regiment. He advanced through the ranks from private to corporal to sergeant, and received his commission as a second lieutenant in 1891. During this time, Dalton took part in conflicts between the U.S. military and American Indians: the Cheyenne Campaign of 1890 and Sioux Campaign of 1891. Later, Dalton was involved in the Spanish–American War, fighting in Cuba during the Santiago Campaign (1898) and also in the subsequent Philippine–American War (1899–1902). Then from 1907–1909, Dalton was part of the U.S. occupation force during the Occupation of Cuba. Dalton also took part in the Occupation of Veracruz (1914) and between 1916–1917 was stationed on the Mexican-United States border during the Pancho Villa Expedition. Dalton was serving as a Major at General Pershing's headquarters when the United States entered World War I in 1917, and from September to October of that year he organized the expeditionary depot in Philadelphia. Dalton then became the General Superintendent of the Army Transport Service in New York from November 1917–1918. He was promoted to Brigadier General of the National Army and commander of the 18th Infantry Brigade, 9th Infantry Division, Dalton then served in France until August 1919. In 1922, Dalton became the Assistant Quartermaster General in Washington D.C., where he remained until his retirement on 7 July 1926.