 In 1943, he was appointed Ambassador Extraordinary and Minister Plenipotentiary to His Majesty the King of Yugoslavia, a post he held until 1946.He was the British Ambassador to China from 1946 to 1950.Stevenson was Her Britannic Majesty's Ambassador to the Kingdom of Egypt from 1950 to 1953 and later on to the Republic of Egypt from 1953 to 1955.He was also a member of the Legislative Council of the Isle of Man from 1955 to 1970, as well as Captain of the Parish of Arbory from 1963 to 1976.