According to Cecil's obituary in The Independent, from childhood he had a close personal relationship with Donald Maclean, and the two both studied at Cambridge and worked together in the Foreign Office.[1] Maclean was a member of the Cambridge Five, who acted as spies for the Soviet Union.[1] There was some speculation that this relationship "cost [Cecil] the promotion to the highest echelons of the diplomatic service which his talents merited."[1] Cecil would later write a biography of Maclean.[1]
Cecil went on to become a reader in Contemporary German History at the University of Reading from 1968 to 1978, and chairman of the Graduate School of Contemporary European Studies from 1976 to 1978,[4] at the University of Reading. From 1968 to 1994 he was chairman of the London-based Institute for Cultural Research (ICR),[a] founded by the writer, thinker and teacher in the Sufimystical tradition, Idries Shah[1][4] (for whom Cecil wrote an obituary).[5] Cecil wrote three monographs for the institute, and also published several books,[4] including The King's Son, co-compiled for Shah's publishing house, Octagon Press.
As well as his interest in Sufism, Cecil had a prior interest in the esoteric work of the Russian mystic, P. D. Ouspensky. Ouspensky lectured in New York, and had been a student of George Gurdjieff whose school became known as the Fourth Way.[1]
The Myth Of the Master Race: Alfred Rosenberg and Nazi Ideology (Dodd, Mead & Company, 1972) ISBN0396065775[10]
Hitler's Decision to Invade Russia (HarperCollins, 1975) ISBN0706701828[11]
The King's Son: Readings in the Traditional Psychologies and Contemporary Thought of Man (co-compiled with Richard Rieu and David Wade, Octagon Press, 1980) ISBN090086088X
A Divided Life: a biography of Donald Maclean (The Bodley Head Ltd, 1988) ISBN0370311299[1][12]
The Masks of Death: Changing Attitudes in the Nineteenth Century (The Book Guild, 1991) ISBN0863326072.