He married Julia Lyndall Weiner, a social worker and sister of Edmund Weiner (deputy Chief Editor of the Oxford English Dictionary) in 1968. They had four children: three sons (1972, 1973 and 1977) – including the journalist and author Hugh Miles – and one daughter (1979). Oliver had eleven grandchildren; the eldest was born in 2006 and the youngest in 2018.
Oliver Miles joined Her Majesty's Diplomatic Service in 1960, serving overseas mainly in the Arab world as well as spending periods at the Foreign and Commonwealth Office in London. In 1964, he was posted as Second Secretary to Amman, and as First Secretary to Makulla in 1966. Miles was appointed Private Secretary to the British High Commissioner in Aden in 1967. In 1970, he was posted to Nicosia and returned to London after three years. He was appointed Counsellor at Jeddah in 1975, and moved to Athens in 1977. He became Head of the FCO's Near East and North African Department in 1980. He was appointed HM Ambassador to Libya in 1984, where he broke off diplomatic relations after the murder of WPC Yvonne Fletcher outside the Libyan embassy in London. Later in 1984, Miles moved to the UK Mission to the United Nations, New York and, from 1985 to 1988, he was Ambassador to Luxembourg.
After two years' secondment at the Northern Ireland Office in Belfast he became the first Director-General of the Joint Directorate for Overseas Trade Services, a new unit set up to improve British Government services to exporters, and travelled widely both in Britain and abroad. At the same time he was a non-executive Director of Vickers Defence Systems.
From 1993 to 1996 Miles was Ambassador to Greece.
Miles was appointed Companion of the Order of St Michael and St George (CMG) in the 1984 New Year Honours.
After retiring from HM Diplomatic Service in 1996 Miles joined MEC International, a consultancy promoting business with the Middle East, and became chairman a decade later. He was for some years president of the Society for Libyan Studies, a learned society under the aegis of the British Academy, and chairman of HOST, a charity which arranges visits to British homes for foreign students in Britain.
From 2004 to 2019 he was Deputy Chairman of the Libyan British Business Council, set up with the approval of the British and Libyan Governments to promote trade and investment.
Subsequently, he wrote a long series of articles that were published in The Guardian. An article in August 2008, entitled "The long road to normalisation", asked rhetorically whether the recently signed compensation agreement between the United States and Libya would work. The article concluded:
The most important compensation issue, Lockerbie, has been settled on the basis that Libya agreed to hand over two suspects for trial in the Scottish courts and to accept responsibility for their actions. One was acquitted, the other convicted, but his conviction has been called into question by the Scottish Criminal Cases Review Commission. There is the possibility of a retrial, and it remains to be seen what effect that might have on the Libya/America soap opera.
On 22 November 2009, The Independent on Sunday published an article by Miles in which he partly questioned the appointment of two British Jewish historians, Sir Lawrence Freedman and Sir Martin Gilbert, to the Iraq inquiry panel because of their background and support for Israel.
- "Oliver Miles, diplomat and Arabist who later criticised Tony Blair over the rebuilding of Iraq after the invasion – obituary". The Telegraph. Telegraph Media Group Limited. 12 December 2019. Retrieved 13 December 2019.
- "MEC International". Archived from the original on 2010-11-05. Retrieved 2009-01-12.
- Levens, R.G.C., ed. (1964). Merton College Register 1900-1964. Oxford: Basil Blackwell. p. 480.
- The Diplomatic Service List 1989 (page 253), HMSO, ISBN 0-11-591707-1
- "No. 49583". The London Gazette. 31 December 1983. p. 4.
- "HOST welcomes international students in the UK!". Retrieved 2009-01-12.
- "In memoriam: Oliver Miles CMG". Libyan British Business Council. Retrieved 13 December 2019.
- Tom Gross (28 April 2004). "Backlash begins against ex-diplomats' "poisonous views" on Iraq, Israel". Retrieved 2009-01-12.
- "Oliver Miles – Profile". London: The Guardian. 2008-03-27. Retrieved 2009-01-12.
- Oliver Miles (2008-08-16). "The long road to normalisation". London: The Guardian. Retrieved 2009-01-12.
- "The key question – is Blair a war criminal?". The Independent on Sunday. London. 2009-11-22. Retrieved 2010-01-12.
- Cesarani, David (29 January 2010). "Britain's affair with antisemitism". The Guardian. London. Retrieved 25 March 2010.