Robin Fearn was born on 5 September 1934, son of Albert Cyprian Fearn and Hilary (née Harrison); he was educated at Ratcliffe College, then University College, Oxford, taking a degree in Modern Languages. In 1961 he married Sorrel Mary Lynne Thomas; they have three sons and one daughter.

After his National Service in the Intelligence Corps (1952-54), Fearn joined the overseas marketing section of Dunlop Rubber Company Limited (1957-61). He then entered Foreign Service in 1961, and his diplomatic career included: Foreign Office (1961-62); Third, later Second Secretary, Caracas [Venezuela] (1962-64); Havana [Cuba] (1965); First Secretary, Budapest [Hungary] (1966-68); Foreign and Commonwealth Office (1969-72); Head of Chancery, Vientiane [Laos] (1972-75); Assistant Head of Science and Technology Department, FCO (1975-76); Counsellor, Head of Chancery and Consul General, Islamabad [Pakistan] (1977-79); Head of South America Department, FCO (1979-82); Head of Falkland Islands Department, FCO (1982); Royal College of Defence Studies (1983); Ambassador to Cuba (1984-86); Assistant Under-Secretary of State (Americas), FCO (1986-89); Ambassador to Spain (1989-94). Sir Robin died in October 2006.