In July 1917, Atkisson was made a major in the National Army, and placed in command of the 30th Engineers, which became the 1st Gas Regiment. This regiment arrived in France on March 10, 1918, and eventually participated in the Aisne-Marne, St. Mihel, and Meuse-Argonne operations. In May 1918 he was made commandant of the Gas Service Experimental Field and Gas Defense School at Hanlon Field near Chaumont, France. Beginning in January 1919, having risen to the rank of colonel, he served in various capacities with the Army of Occupation. For his service in the war, Atkisson was awarded the Distinguished Service Medal, the Purple Heart, and the Distinguished Service Order of Great Britain.