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Hugh Sinclair

1873 – 1939

Royal Navy admiral

Intelligence officer
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About Hugh Sinclair

Lived 1873 – 1939 (aged 66). Hugh Sinclair was an intelligence officer.

Admiral Sir Hugh Francis Paget Sinclair, (18 August 1873 – 4 November 1939), known as Quex Sinclair, was a British intelligence officer. He was Director of British Naval Intelligence between 1919 and 1921, and he subsequently helped to set up the Secret Intelligence Service (SIS now commonly called MI6).

Career Sinclair was educated at Stubbington House School and joined the Royal Navy as a cadet aged 13 on 15 July 1886. He was promoted to lieutenant on 31 December 1894.

He entered the Naval Intelligence Division at the beginning of the First World War. He became Director of Naval Intelligence in February 1919 and Chief of the Submarine Service in 1921. He became the second director of SIS in 1923. He was promoted vice-admiral on 3 March 1926 and full admiral on 15 May 1930. Sinclair also founded Government Code and Cypher School in 1919.

Beginning in 1919 he attempted to absorb the counterintelligence service MI5 into the SIS to strengthen Britain's efforts against Bolshevism, an idea that was finally rejected in 1925. The SIS remained small and underfunded during the interwar years.

In 1938, with a second war looming, Sinclair set up Section D, dedicated to sabotage. In spring 1938, using £6,000 of his own money, he bought Bletchley Park to be a wartime intelligence station.

Sinclair was asked in December 1938 to prepare a dossier on Adolf Hitler, for the attention of Lord Halifax, the Foreign Secretary, and Neville Chamberlain, the Prime Minister. In the dossier, which was received poorly by Sir George Mounsey, the Foreign Office assistant undersecretary, who believed that it did not gel with Britain's policy of appeasement, Sinclair described Hitler as possessing the characteristics of "fanaticism, mysticism, ruthlessness, cunning, vanity, moods of exaltation and depression, fits of bitter and self-righteous resentment; and what can only be termed a streak of madness; but with it all there is a great tenacity of purpose, which has often been combined with extraordinary clarity of vision".

Sinclair became seriously ill with cancer, causing Alexander Cadogan to note on 19 October 1939, that he was "going downhill". On 29 October, Sinclair underwent an operation for his cancer and died on 4 November 1939, aged 66, five days before the Venlo incident.

Family Hugh was the son of Admiral Frederick Beauchamp Paget Seymour, 1st Baron Alcester and Agnes Sinclair. In his will, Lord Alcester left the balance of his estate to Agnes Sinclair for her lifetime. On her death, two fifths were left to Frederick Charles Horace Sinclair and one fifth each to Hugh Francis Paget Sinclair, Claude Hamilton Sinclair and Evelyn Beauchamp Sinclair.

In 1907 Hugh married Gertrude Attenborough; they had two sons. They were divorced in 1920.

Awards and decorations

1911 King George V Coronation Medal 1916 Companion of the Order of the Bath 1918 3rd Class, Order of the Rising Sun 1918 Officer, the Legion of Honour 1935 Knight Commander, the Order of the Bath 1937 King George VI Coronation Medal

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Important facts

Birth century
Occupation
Intelligence officer
Education
Stubbington House School
Positions held
Chief of the Secret Intelligence Service
Employers
Secret Intelligence Service
Awards
Knight Commander of the Order of the Bath; Companion of the Order of the Bath
Also known as
Sir Hugh Francis Paget Sinclair, Quex Sinclair

People in Hugh Sinclair's life

Named in this biography and alive at the same time

Contemporaries

People whose lives overlapped Hugh Sinclair's

Frequently asked questions

Who was Hugh Sinclair?

Royal Navy admiral (1873–1939)

When was Hugh Sinclair born?

Hugh Sinclair was born on 18 August 1873 in Southampton.

When did Hugh Sinclair die?

Hugh Sinclair died on 4 November 1939 in Marylebone.

What was Hugh Sinclair's occupation?

Hugh Sinclair was an intelligence officer.

Sources & further reading

· Wikipedia: Hugh Sinclair

· Wikidata: Q5932688

· DBpedia: Hugh Sinclair

Cite this page

APA: Biography.guide. (2026). Hugh Sinclair. https://biography.guide/hugh-sinclair-intelligence-officer/

MLA: "Hugh Sinclair." Biography.guide, https://biography.guide/hugh-sinclair-intelligence-officer/.

Chicago: "Hugh Sinclair." Biography.guide. https://biography.guide/hugh-sinclair-intelligence-officer/.

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