Born on 20 December 1886 at Mooresville, North Carolina, he was educated at Davidson College and the University of Maryland, and served as resident surgeon at the University of Maryland Hospital, Baltimore in 1909. In 1916 he was called to the Mayo Clinic, Rochester, Minnesota, as assistant surgeon at St Mary's Hospital, becoming surgeon in 1922, and was associate professor of surgery in the University of Minnesota from 1926 to 1933. He then moved to Lexington, Kentucky as surgeon to St Joseph's Hospital, and in 1941 was appointed professor of clinical surgery in the University of Louisville. Rankin was a leading authority on abdominal cancer, and wrote much in the professional journals, especially on the surgery of the colon and rectum. He served in France as a Major, US Medical Corps in 1917-18 and in many theatres of war during 1941-45 with the rank of Brigadier-General. He was President successively of the American Medical Association, the American Surgical Association, and the American College of Surgeons. Rankin married Edith, daughter of Charles H Mayo, Hon FRCS. He died at Lexington, Kentucky during his term of office as President of the American College on 22 May 1954 aged 67