Born 7 January 1871, the son of Albert Horder, of Shaftesbury. He was educated privately, and at the University of London and St Bartholomew's Hospital, London.
Horder served as Captain (temp. Major) Royal Army Medical Corps; Adviser to Minister of Food and President of Food Education Society; Chairman of Committee advising Ministry of Labour and National Service on medical questions connected with Recruiting; Chairman of Shelter Hygiene Committee of Ministry of Home Security and Ministry of Health; Hon. Consulting Physician to Ministry of Pensions; Consulting Physician Cancer Hospital, Fulham; President, Harveian Society of London; Chairman of British Empire Cancer Campaign and Chairman Advisory Scientific Committee; Chairman of Advisory Committee, Mount Vernon Hospital; President of Fellowship of Medicine; Consulting Physician to the Royal Orthopædic Hospital, to the Royal Northern Hospital and to the Hospitals of Bury St Edmunds, Swindon, Bishop's Stortford, Leatherhead, Beckenham and Finchley. He was also a member of numerous associations and committees.
He was awarded GCVO, 1938; (KCVO, 1925); Kt, 1918; MD; BSc; Hon. DCL (Dunelm.); Hon. MD (Melbourne and Adelaide); FRCP. In 1923 he was created Thomas Jeeves Horder, Baronet of Shaston; in 1933 created, 1st Baron Horder, of Ashford in the County of Southampton.
He also held the positions of Deputy Lieutenant County of Hampshire; Extra Physician to the Queen (formerly Extra Physician to King George VI); and Consulting Physician to St Bartholomew's Hospital.
In 1902 Horder married Geraldine Rose Doggett (died 1954), of Newnham Manor, Hertfordshire. He died 13 August 1955.
Publications
Clinical Pathology in Practice; with a short account of Vaccine-Therapy, Oxford Medical Publications. 1907; Cerebro-spinal Fever, Oxford War Primers 1915; Medical Notes, London, 1921; A Preliminary Communication concerning the "Electronic Reactions" of Abrams with special reference to the "Emanometer" Technique of Boyd. Read before ... the Sections of Medicine and Electro-Therapeutics of the Royal Society of Medicine by Sir T. Horder on behalf of M. D. Hart, C. B. Heald, etc. J. Bale & Co, London, 1925; with A E Gow, The Essentials of Medical Diagnosis, Cassell & Co, London, 1928; Obscurantism, Watts & Co, London, 1938; Health & a Day. Addresses, J. M. Dent & Sons: London, 1937; Rheumatism. Notes on its causes, its incidence and its prevention; with a plan for national action in collaboration with the Empire Rheumatism Council, H. K. Lewis & Co, London, [1941]; Fifty Years of Medicine. [An expanded version of three Harben lectures delivered at the Royal Institute of Public Health and Hygiene, 1952.], Gerald Duckworth & Co, London, 1953; with Sir Charles Dodds and T Moran, Bread. The chemistry and nutrition of flour and bread, with an introduction to their history and technology, Constable, London, 1954.