George Donald King McCormick (11 December 1911 – 2 January 1998) was a Britishjournalist and popular historian, who also wrote under the pseudonyms Richard Deacon and (for works in Chinese translation) Lichade Diken.
McCormick's reliance on an informal network of oral informants, and his eye for a good story, means that it is often difficult to judge the reliability of his more controversial claims. In 1979 he claimed that Rudolf Peierls had been under investigation as a Soviet agent, and was forced to make an out-of-court settlement when Peierls sued him. (The equally controversial Rupert Allason, who once worked for McCormick, has continued to press this particular claim after Peierls's death.) McCormick also claimed that the early-twentieth-century economist Arthur Pigou had been a Russian agent, and to be in possession of Pigou's journal: no such journal has surfaced since McCormick's death.
John Dee: Scientist, Geographer, Astrologer and Secret Agent to Elizabeth I. London: Muller, 1968.
A History of the British Secret Service. London: Muller, 1969. New York: Taplinger, 1970. Reprinted in paperback, London: Grafton, 1991.
A History of the Russian Secret Service. New York: Taplinger, 1972. London: Muller, 1972.
The Chinese Secret Service. New York: Taplinger, 1974. [pb] Revised and updated. London: Grafton Books, 1989.
The Hell-Fire Club : the story of the amorous Knights of Wycombe. London: Sphere,1975.
Matthew Hopkins: Witchfinder General. London: F. Mueller, 1976.
The Israeli Secret Service. London: Hamish Hamilton, 1977.
The Silent War: A History of Western Naval Intelligence. Newton Abbot, UK: David & Charles, 1978. New York: Hippocrene Books, 1978.
The British Connection: Russia's Manipulation of British Individuals and Institutions, London: Hamish Hamilton. 1979. Later withdrawn.
Escape! London: BBC, 1980.
Love In Code, or, How to Keep Your Secrets. London: Eyre Methuen, 1980.
Kempai Tai: A History of the Japanese Secret Service. London: Muller, 1982. New York: Beaufort Books, 1983. Revised and updated edition, Tokyo: Charles Tuttle Books, 1990.
With My Little Eye: The Memoirs of a Spy-Hunter. London: Frederick Muller, 1982.
"C": A Biography of Sir Maurice Oldfield. London: MacDonald, 1985.
The Cambridge Apostles: A History of Cambridge University's Elite Intellectual Secret Society. New York: Farrar, Straus, 1986.
Spyclopedia: The Comprehensive Handbook of Espionage. New York: Morrow, 1987.
The Truth Twisters. London: Macdonald, 1987.
The Greatest Treason: The Bizarre Story of Hollis, Liddell and Mountbatten. London: Century, 1990. (A 1989 printing had resulted in a libel suit and was withdrawn; this edition had the offending material withdrawn.)
Super Spy: The Man Who Infiltrated the Kremlin and the Gestapo. UK: Futura, 1990.