 Following his military service in World War II, Mitchell completed a bachelor's degree in Optometry at Hobart College in 1949, and earned a master's degree from Columbia University in 1950.In the early 1950s he founded an optometry practice in Herkimer, New York.In 1954, he was elected to the Herkimer City Council (1954–1957), and served as Mayor of Herkimer from 1957–1960.