Sir Gerald Kennedy Nicholas Trevaskis entered the colonial service as an administrative cadet, Northern Rhodesia in 1938. During the Second World War he enlisted with the Northern Rhodesian Regiment, was captured by Italian forces at Tug Aqan, British Somaliland in 1940, was seconded to British Military Administration, Eritrea, 1941-1948, and was made Senior Divisional Officer, Assab, 1943. After the war, he served as a member of the British delegation to the Four Power Commission of Investigation into ex-Italian Colonies, 1947-1948. He worked as District Commissioner at Ndola, Northern Rhodesia and Liaison Officer for the United Nations Commission, Eritrea, 1950. He served as Political Officer, Western Aden Protectorate, 1951, Deputy British Agent from 1952 and British Agent to Western Aden Protectorate from 1954. In 1957 he was a member of the British Delegation at the Anglo-Yemeni meeting in London. He held the post of High Commissioner for Aden and the Protectorate of South Arabia, 1963-1965. Awarded the OBE and KCMG, he published Eritrea: A Colony in Transition, 1941-52 (Oxford, Oxford University Press, 1960) and Shades of Amber: A South Arabian Episode (London, Hutchinson, 1968). In 1945 he married Sheila James Harrington.