He served a two-year tour of duty as a tank officer in the 2nd Armored Division of the U.S. Army and then earned a divinity degree from Southwestern Baptist Theological Seminary in 1955.
[3] After reading a book by Albert Schweitzer, he changed vocations to medicine and enrolled in the University of Texas Southwestern Medical School in Dallas,[3] from which he received his M.D.
Duke's academic career began in 1966 as an assistant professor of surgery at UT Southwestern Medical School and later at the Columbia University College of Physicians and Surgeons in New York.
He also took some time to pursue graduate studies in chemical engineering, biochemistry and computer sciences at Columbia University under the auspices of an NIH Special Fellowship.
[10] Duke's efforts to educate the public in health issues and tireless work as a crusader against trauma brought him into serious consideration for the position of Surgeon General of the United States in 1989.
The University of Texas Medical School at Houston Department of Surgery sponsored a scholarship fund in honor of Duke, aimed towards students wishing to research and train in the field of trauma.
He served as president of the Boone and Crockett Club, the oldest conservation organization in the United States, and the Foundation for North American Wild Sheep.
Duke has been featured on such programs as PM Magazine, NBC Nightly News, The Today Show and the Buck James television series, which was based on him.