Spaulding was promoted to
major and
lieutenant colonel in 1917. In 1918, he was promoted to
colonel, and he performed temporary duty as inspector of artillery units preparing to depart for combat in France. During the First World War, Spaulding served in France,
Luxembourg, and Germany as commander of the 161st, 55th, and 165th Field Artillery Brigades with the temporary rank of brigadier general. After the war, he was chief of the historical section on the
American Expeditionary Forces staff with the temporary rank of brigadier general. He was professor of military science at
Harvard University from 1929 to 1935, and received his
M.A. degree from Harvard in 1932. Spaulding taught again at the war college from 1935 to 1939. He retired in June 1939 after attaining the mandatory retirement age of 64. Legislation passed in 1930 permitted general officers from World War I to retire at their highest wartime rank, and at retirement Spaulding was promoted to brigadier general on the retired list. ==Later years and death==