At age 18, with the onset of WW II, Mitchell volunteered for flight training with the Army Air Corps, serving overseas in the Pacific Theatre.

[1] Between his years of service in the two military branches, Mitchell followed in the footsteps of his father, attended the University of Georgia School of Law in Athens and earned LL.B.

While still in the Air Force, Mitchell ran for the position of Cherokee Judicial Circuit solicitor general, and was elected.

Upon the death of U.S. Representative Henderson Lovelace Lanham, in November 1957, Mitchell announced his intention to run for Georgia's 7th congressional district.

[2] He ran as a Democrat and won the special election to fill Lanham's term in the 85th United States Congress.