Background
Campbell was the second son of Sir Guy Campbell, 3rd Baronet (see Campbell baronets), by Nina, daughter of Frederick Lehmann.
Campbell was the second son of Sir Guy Campbell, 3rd Baronet (see Campbell baronets), by Nina, daughter of Frederick Lehmann.
He was educated at Eton and graduated from Magdalen College, Oxford, in 1912 with a Bachelor of Arts.
In 1939, Campbell was appointed Envoy Extraordinary and Minister Plenipotentiary to the Kingdom of Yugoslavia, a post he held until 1941, when he became Envoy Extraordinary and Minister Plenipotentiary to Washington to 1944. He became Assistant Under-Secretary of State for the Foreign Office in 1945, and served as the United Kingdom"s ambassador to Egypt from 1946 to 1950. He was invested as a Privy Counsellor in 1950.