Douglas Harold Mitchell was born in Bethanga, Victoria, Australia, on 11 September 1901. He was educated at Bethanga State School, Wesley College, Melbourne, and Melbourne University. He graduated MB BS in 1926. He came to England in 1930 and was a resident at Ipswich and Northampton Hospitals. He obtained the FRCS in 1931. He married Renée Isabel Campbell-Howe and they had one daughter and two sons, one of whom is a physician. He entered the RAMC in 1941 with the rank of Major. He died on 21 June 1973, aged 72 years.