Mervyn Brown was born 24 September 1923; he was educated at Ryhope Grammar School, Sunderland and St John's College, Oxford. In 1949 he married Elizabeth Gittings.
After served in the Royal Artillery, 1942-45, Brown entered the Foreign Service in 1949. His diplomatic career included: Third Secretary, Buenos Aires [Argentina], 1950; Second Secretary, UK Mission to United Nations, New York [United States], 1953; First Secretary, Foreign Office, 1956; Singapore, 1959; Vientiane [Laos], 1960; again in Foreign Office, 1963-67; Ambassador to Madagascar, 1967-70; Inspector, Foreign and Commonwealth Office, 1970-72; Head of Communications Operations Department, FCO, 1973-74; Assistant Under-Secretary of State (Director of Communications), 1974; High Commissioner in Tanzania, 1975-78, and concurrently Ambassador to Madagascar; Minister and Deputy Permanent Representative to United Nations, 1978; High Commissioner in Nigeria, 1979-83, and concurrently Ambassador to Benin.
He was awarded the KCMG in 1981 (CMG 1975); OBE 1963.