Jack Richard DeWitt was born December 15, 1918 in Muskogee, Oklahoma. His family moved to Wisconsin in his youth and he graduated from Lancaster (Wisconsin) High School in 1936. He enrolled at the University of Wisconsin-Madison, received a bachelor's degree in economics in 1940, and immediately entered the law school. In 1942 he stood two credits short of a law degree and made an arrangement with the University whereby they waived the final two credits and his mandatory apprenticeship in exchange for DeWitt writing an extra paper and enlisting into the Army.
DeWitt joined the Army in March 1942 and did early training at Fort Sheridan, Illinois and Camp Chaffee, Arkansas. Later that year DeWitt attended Officer's Candidate School (OCS) at Fort Knox, Kentucky and was commissioned as an officer on December 12, 1942. Assigned to the 14th Armored Division, he went back to Camp Chaffee to train before being deployed to the European Theater.
In October 1944 DeWitt, a company commander in the 19th Armored Infantry Battalion, went over to Europe along with the rest of the 14th Armored Division. He served primarily in the Rhineland campaign, and won several prestigious awards including the Distinguished Service Cross, Silver Star, and the British Military Cross. His unit helped to liberate the German concentration camp at Dachau, and DeWitt remained in Germany with occupation forces until returning to the United States in December 1945.
DeWitt remained with the Army, serving in the Reserves with the 84th Airborne Division and rising to the rank of brigadier general in 1966 before retiring in 1967. He served on the faculty of the University of Wisconsin Law School and remains a practicing attorney in Madison.
