Born at Worksop, Notts, 14 June 1860, son of John Alfred Coates, he received his medical education at the London Hospital, where he gained a scholarship in anatomy and was a surgical prizeman. He held resident appointments there, and in 1884 set up in general practice in Moss Side, Manchester. He was appointed captain in the Volunteer Medical Staff Corps on its formation in 1886 and was commanding officer of its 4th division in 1897. He was instrumental in forming a Territorial RAMC unit in Manchester in 1908, and was ADMS of the East Lancashire Territorial Division 1903-12 and ADMS of Western Command 1914-18, retiring as Colonel AMS. He was chairman of the East Lancashire Association TA, chairman of the East Lancashire joint committee of the Order of St John and the British Red Cross Society, chairman of the East Lancashire Homes for Totally Disabled Soldiers and Sailors, a member of council of the British Red Cross Society and of the council of the Voluntary Aid Detachment. For his services to the Order of St John of Jerusalem he was made a Knight of the Order. Coates served as president of the Manchester Medical Society and vice-president of the Barrowmore Tuberculosis Colony, was a member of the British Medical Association for sixty years and president of the venereal diseases section at the annual meeting in Manchester in 1929. In 1911 he supported the National Medical Union in opposition to Lloyd George's Health Scheme. He retired from active practice owing to failing sight in 1953 and at a Council meeting on 12 May 1960 received the congratulations of Council on the attainment of his hundredth birthday. He married in 1896 Leonora, daughter of Frederick Stilwell Freeland of Chichester, who died in 1949 survived by two sons and a daughter. Coates was a man of spare build and medium height with a neat military figure, who commanded attention in any company by virtue of his personality. He died at Ingleside, Whalley Range, Manchester on 13 January 1962 aged 101. Publications: Two cases of intravenous injection of fluids for severe haemorrhage. *Lancet* 1882, 2, 1110. The duty of the medical profession in the prevention of national deterioration. Presidential address, Manchester Medical Society. *Brit med J* 1909, 1, 1045. Early treatment of Syphilis. *Brit med J* 1910, 1, 1093.