|Died||11 June 1947 (aged 70)|
|Other names||Uncle Claude|
|Allegiance||United Kingdom of Great Britain and Ireland|
Lieutenant-Colonel Sir Claude Edward Marjoribanks Dansey, KCMG (10 September 1876 – 11 June 1947), also known as Colonel Z, Haywood, Uncle Claude, and codenamed Z, was the assistant chief of the Secret Intelligence Service known as ACSS, of the British intelligence agency commonly known as MI6, and a member of the London Controlling Section. He began his career in intelligence in 1900, and remained active until his death.
Dansey was born in 1876 at 14 Cromwell Place into a dysfunctional family of nine children, their mother, Hon Eleanor Dansey, daughter of Robert, 2nd Baron Gifford, who was probably an alcoholic. The siblings were subjected to military discipline at the hands of their soldier father (Edward Mashiter Dansey), with punishments that included beatings even for minor misbehaviour. At the age of 17 he became sexually involved with Robert Baldwin Ross, and Lord Alfred Douglas, narrowly avoiding exposure and imprisonment. He was educated at Wellington College and the English College, Bruges, Belgium.
In 1895 he joined the Matabeleland Regiment of the British South African Police. On 13 June 1898 he joined the militia as second lieutenant in the 5th and 6th battalion Lancashire Fusiliers, being promoted to lieutenant on 9 November. On 16 August 1899 he was seconded for service with the British North Borneo Company. He transferred to the regular army when he was appointed a second lieutenant of the 2nd battalion on 24 February 1900, followed by promotion to lieutenant on 15 August 1900. On 1 March 1902 he was again seconded, as a Staff Lieutenant for Intelligence in South Africa, then on 24 June he was appointed aide-de-camp to the Brigadier-General commanding the Harrismith District, Charles James Blomfield. He was transferred from a supernumerary lieutenancy onto the establishment of his regiment on 17 September 1902. On 4 November 1904 he was seconded for "special extra-regimental employment" as a Political Advisor in the British Somaliland Protectorate and on 24 October 1906 he resigned his commission. On 10 April 1907 he was promoted to captain on the Reserve of Officers.
He was recruited by MI5 and put in charge of "port intelligence" and the surveillance of civilian passengers during World War I. He was "inadvertently" responsible for allowing Leon Trotsky to return to Russia in 1917. He helped set up the first American military intelligence service in 1917. He became deputy to Stewart Menzies, chief of MI6 (SIS) in November 1939 and retired in 1945.
Dansey married Mrs Pauline Monroe Ulman (maiden surname Cory) in 1915 and they were later divorced. He married Mrs Frances Gurney Rylander (Maiden surname Wilson) in 1945. There were no children. Dansey died on 11 June 1947 in Bath, Somerset.
- Pronounced Marchbanks, see Clan Marjoribanks
- Sturgis, Matthew (2018). Oscar: A Life (First ed.). London: Head of Zeus. p. 491. ISBN 9781788545976.
- "No. 26983". The London Gazette. 1 July 1898. p. 3986.
- "No. 27021". The London Gazette. 8 November 1898. p. 6513.
- "No. 27108". The London Gazette. 15 August 1899. p. 5123.
- "No. 27168". The London Gazette. 23 February 1900. p. 1258.
- "No. 27220". The London Gazette. 14 August 1900. p. 5035.
- "No. 27436". The London Gazette. 23 May 1902. p. 3382.
- "No. 27427". The London Gazette. 22 April 1902. p. 2693.
- "No. 27496". The London Gazette. 18 November 1902. p. 7340.
- "No. 27474". The London Gazette. 16 September 1902. p. 5962.
- "No. 27737". The London Gazette. 22 November 1904. p. 7607.
- "No. 27960". The London Gazette. 23 October 1906. p. 7112.
- "No. 28011". The London Gazette. 9 April 1907. p. 2415.
- Richard Norton-Taylor (5 July 2001). "MI5 detained Trotsky on way to revolution". The Guardian.
- Simkin, John (January 2020). "Claude Dansey". Spartacus Educational. Retrieved 20 October 2020.
- Brown, Anthony Cave (1987) 'C' The Secret Life of Sir Stewart Graham Menzies, spymaster to Winston Churchill, Macmillan Publishing Company, New York,
- Andrew, Christopher (1986). Her Majesty’s Secret Service: The Making of the British Intelligence Community, .New York: Viking, ISBN 9780670809417.
- Hastings, Max (2015). The Secret War: Spies, Codes and Guerrillas 1939 -1945 (Paperback)
|url=(help). London: William Collins. ISBN 978-0-00-750374-2.
- Marshall, Robert (1988). All The King's Men. London: Collins. Marshall declared the culprit was homosexual, allegedly, and Freemason, Deputy Head of MI-6, Sir Claude Edward Marjoribanks Dansey (1876-1947.)
- Read, A.; Fisher, D. (1984). Colonel Z: The Life and Times of a Master of Spies. Hodder & Stoughton. ISBN 0-340-26910-3.
- Volkman, E. (1994). Spies: the Secret Agents Who Changed the Course of History. John Wiley & Sons. ISBN 0-471-19361-5.