Loyal Edward Davis was born on 17 January 1896 in Galesburg, Illinois, the son of Al Davis, a railroad engineer who had worked from the age of seven. It was assumed by all in that small community, except his father, that he would earn his living on the Burlington Railroad. Al, however, frequently advised him to prepare to work with his head rather than his back. After grade school he attended Knox College, earning a little in the vacations in the passenger traffic office of the railroad as did a young Harvard medical student. Perhaps his conversations with that student turned his thoughts to medicine. He graduated MD, Northwestern University Medical School in 1918 and spent an intern year at Cook County Hospital, Chicago, before joining the practice in Galesburg of Dr Baird, the local family doctor. Davis had been introduced to Miss Pearl McElroy during his intern year and they married in Chicago. They settled in Galesburg where Davis gathered experience. Baird had picked up some surgical expertise in the clinic of J B Murphy and patients were referred to him by nearby doctors, with whom Baird shared the fee. Davis objected to this unethical approach and a visit to his former teacher, Allen Kanavel, led to his becoming Kanavel's part-time assistant with access to the laboratory of S W Ranson, Professor of Anatomy, for teaching and an investigation into decerebrate rigidity, experimental work which led to his degree of Master of Science (MS) in 1921 and to his PhD in 1923. His absorption in this work led to difficulty in his marriage, and a divorce. Visits were arranged to Walter Dandy in Baltimore, Frazier in Philadelphia and Cushing in Boston with whom he spent a year as associate, returning to Chicago in 1925 as the first specialist neurosurgeon there. Pollock and Davis came to London in 1927 to present their work on decerebrate rigidity and Davis met Edith Luckett Robbins on the SS *New York* on the way over. Edith had a daughter, Nancy, then aged four. Davis and Edith were married in Chicago in May, 1929. She transformed his domestic life, mellowed his single minded approach, and supported him professionally. He became a Fellow of the American College of Surgeons in 1928, Professor of Surgery and Director of the Research Laboratories, and Chairman of the Divisions of Surgery at the Medical School and at Passavant Memorial Hospital, in 1933. He held these posts for 30 years and Davis succeeded Kanavel as editor of *Surgery, gynaecology and obstetrics* until 1981 and edited *Christopher's Textbook of surgery* from 1956 to 1968. He became a Governor of the American College of Surgeons in 1946, a Regent in 1950, Chairman of the Board of Regents in 1960 and President of the College in 1962. He served also as President of the American Surgical Association and of the Society of Neurological Surgeons. The honorary degree of DSc was conferred on him by Knox College and by Temple University, he was awarded the Alumni Medal by Northwestern University and he became an Honorary Fellow of the College in 1955 and of the Edinburgh College in 1958. Professor Davis was commissioned in the American Army in 1942, and came to Britain as Chief Consultant in Neurosurgery of the (US) European Theater of Operations. He joined his British colleagues on a surgical mission to Moscow in 1943, and he and his wife were moved and delighted when Northwestern University established the Loyal and Edith Davis Professorship of Surgery. On 14 July, 1981, the President and Council of the Royal College of Surgeons in Ireland travelled to the Irish Embassy in Washington to confer their Honorary Fellowship on him. Davis' son-in-law, President Ronald Reagan, addressing the guests at a dinner that evening, including 28 surgeons and their wives from Ireland, north and south, said to the President of the College, 'You have honoured one of the most distinguished citizens of our country, and we are not at all bothered that your Charter came from George III, shortly after he had an argument with us.' Loyal Davis died on 19 August, 1982, survived by his wife Edith, his son Richard, a neurosurgeon in Philadelphia, and his daughter, Nancy Davis Reagan, America's First Lady.