Henry Galton Darwin CMG (6 November 1929 – 17 September 1992) was a British lawyer and diplomat specialising in international law.
He served as assistant Legal Adviser to the Foreign Office 1954-1960 and again 1963-1967, at which time he was one of the three drafters of the Partial Nuclear Test Ban Treaty,[2] being flown to Moscow in July 1963 to advise Lord Hailsham on the drafting when negotiations were successful;[3] between 1960 and 1963 he was Legal Adviser to the British Embassy in Bonn, West Germany.
He was then Legal Counsellor to the UK Mission to the United Nations in Manhattan, New York 1967-1970, before returning to the Foreign and Commonwealth Office (FCO) 1970-1973.
He played a major role in the third United Nations Conference on the Law of the Sea (UNCLOS III), which took place from 1973 through 1982, and was a member of the Preparatory Commission after 1982.
At the time of his death he was leading a group examining legal issues connected with the former Yugoslavia.