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The Papers of William F Clarke

Reference Code: GBR/0014/CLKE

Scope and Contents

The papers relate to the setting up of Room 40 and the Naval Intelligence's code-breaking activities in the First World War and to Clarke's service in the Government Code and Cypher School from 1922 to 1945.


  • Creation: 1914 - 1959


Conditions Governing Access

The collection is open for consultation by researchers using Churchill Archives Centre, Churchill College, Cambridge.

Conditions Governing Use

Researchers wishing to publish excerpts from the papers must obtain prior permission from the copyright holders and should seek advice from Archives Centre staff.

Biographical / Historical

William Clarke was born on 22 May 1883, the son of the solicitor-general Sir Edward George Clarke and his wife, Kathleen Mathilda Bryant. He was the youngest of three children and the only child of his father's second marriage. Educated at Harrow School and Magdalen College, Oxford (1902-5), Clarke was called to the bar in 1906. On 31 July 1907 he married Dorothy Mainland: they had one son and two daughters.

When war broke out, Clarke left the law for the Navy. In February 1915 he was commissioned as an assistant paymaster (later promoted to paymaster lieutenant-commander). Then in early 1916 the director of naval intelligence, Captain [William] Reginald Hall, recruited him into the new code-breaking unit Room 40. Clarke was particularly good at analysing information, and together with his colleague Frank Birch, he was selected to write a history of Room 40. However, due to Clarke's rather outspoken approach, the history was never published.

In 1919 Clarke joined the Government Code and Cypher School (GCCS), the successor to Room 40 and its War Office counterpart. In 1924 he made a return to more specifically naval work when he was promoted to head the new naval section within the GCCS, a post which Clarke retained until 1941. The GCCS moved to Bletchley Park during the Second World War and Clarke had an important role in the successful decryption of the German and Italian (Enigma) machine codes, particularly devoting himself to Italian naval codes, 1939-40. He retired after the war in October 1945 and died on 5 February 1961.


3 file(s)

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Other Finding Aids

A copy of this finding aid is available for consultation at Churchill Archives Centre, Cambridge and the National Register of Archives, London.

Immediate Source of Acquisition

This small collection was given to Churchill College Archives Centre in September 1980 by Judge Edward Clarke, QC, the son of William F. Clarke, through the good offices of Patrick Beesly.

Related Materials

Further papers of William Clarke are held by the National Archives in series HW3, Government Code and Cypher School and predecessors, 1914-1945.


This finding aid was adapted by Katharine Thomson of Churchill Archives Centre in February 2005 from an existing catalogue. Biographical information was taken from Joseph A. Maiolo's essay, ‘Clarke, William Francis (1883-1961)’, Oxford Dictionary of National Biography, Oxford University Press, 2004.


Clarke, William Francis, 1883-1961, Intelligence Officer


2005-02-16 08:54:14.560000+00:00
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Repository Details

Part of the Churchill Archives Centre Repository

Churchill Archives Centre
Churchill College
Cambridge Cambridgeshire CB3 0DS United Kingdom
+44 (0)1223 336087