Denig was born 29 September 1884 in Clinton, New York. He attended St. Johns School in Manlius, New York, and the University of Pennsylvania. On 29 September 1905, he was appointed as a second lieutenant in the Marine Corps. After studying at the School of Application, Annapolis, Maryland, in 1906, he was ordered to a Provisional Marine Battalion being assembled at Norfolk, Virginia, for duty with the Army in the Cuban Pacification, where he served until November 1907. While leading his men in cleaning out enemy machine guns and snipers from the area around the Medeah Farm in France, Maj Denig was wounded on 3 October 1918. For remaining in action until the mission was accomplished, he earned the Army Distinguished Service Cross and the Navy Cross, the Nation’s second highest decorations.
However, BGen Denig was immediately recalled to active duty and assigned to Marine Corps Headquarters in Washington, D.C., where he was given the task of organizing Division of Public Relations. BGen Denig is credited with “fathering” the idea of combat correspondents in the American armed forces. For his work as director of the Division of Public Relations throughout World War II, he earned the Legion of Merit. Brigadier General Denig retired for a second time on 1 December 1945, after serving more than 40 years in the Marine Corps. He passed away at the age of 94 on 25 July 1979 in Los Altos, California.