 After the 1926 season Simpson moved to Iowa State University, coaching the track team there until 1937; his students there included NCAA mile champions Ray Conger and Ray Putnam.In 1939 Simpson became a coach and athletic director in Hungary, where he stayed for the next years despite World War II.Simpson re-enlisted in the U.S. Army in 1942 with the rank of captain, gaining promotion to major in 1944.