Declassified Documents Online: Twentieth-Century British Intelligence
British Intelligence Files for Researchers
From the international machinery of espionage and twentieth-century warfare to personal surveillance and Cold War intelligence, this uniquely broad view of the interests of the British government, her allies, and her enemies is sourced from five government departments and totals around 500,000 pages.
Twentieth-Century British Intelligence, An Intelligence Empire brings together files from the UK National Archives covering intelligence and security matters from 1905-2002. Material has been sourced from the UK Ministry of Defence, the Cabinet Office, the Colonial Office, MI5 (British Domestic Security Service), and the SOE (Special Operations Executive), reflecting an intelligence network that reached from the UK and Europe to Africa, the Middle East, Canada, Asia, and Australia during a century of global conflicts, high-stakes diplomacy, and political upheaval. These documents cover the development of British intelligence and its impact on policy from its earliest days, through Room 40 in the First World War and the activities of the Security Services throughout the British Empire during WWII, to the geopolitics of the Cold War and decolonization.
Intelligence files, previously closed to scholars, represent an under-studied aspect of our recent past and provide exciting opportunities for new research.
Declassified Documents: Twentieth Century British Intelligence, An Intelligence Empire brings together files from five UK government departments to provide researchers with access to detailed, previously classified information on the intelligence services of Britain and her Empire throughout the twentieth century.
The Security Service (MI5): KV 2, KV 3 & KV 4
Personal, Subject and Policy files dating from 1905-1978. MI5 handled intelligence gathering within the British Empire and the Commonwealth. The selected subseries of KV 2 holds personal files on subjects of Secret Service enquiries, whilst KV 3 contains subject files on espionage activities of groups or other intelligence organizations, including the only subject files known to have survived from the First World War period. KV 4 holds section histories and policy files.
The Ministry of Defence: Communications and Intelligence Records: DEFE 21, DEFE 26, DEFE 28, DEFE 31, DEFE 41, DEFE 44, DEFE 60, DEFE 62, DEFE 63 & DEFE 64
These series include registered files, reports and memoranda of the Directorate of Scientific Intelligence, the Defence Intelligence Staff and the Defence Signals Staff focused on the technical and scientific interests of the British government from the Second World War to the decades of the Cold War and the Atomic Age. The intelligence assessments and reports include those gathered post-war in Allied-occupied Germany, such as interviews with German scientists. With files dating from 1912-2002, these series bring the coverage up to the end of the twentieth century, and include defence records on the Falklands, the Middle East, UFO incidents and details of Soviet weapon systems.
The Special Operations Executive: HS 7 & HS 8
These are records of the Ministry of Economic Warfare and the Special Operations Executive (SOE), which functioned during WWII to promote sabotage and subversion, and assist resistance groups in enemy-occupied territory, famously directed by Winston Churchill to "Set Europe ablaze!" Records date from 1935-1988 and include histories & war diaries in HS 7, and headquarters records in HS 8.
The Colonial Office: Intelligence and Security Departments: Registered Files (ISD Series): CO 1035
This series contains registered files of the Colonial Office relating to the security of British colonies, and intelligence on colonial matters and decolonization, including reports by Security Intelligence Advisors throughout the British Empire, and assessments from the Joint Intelligence Committee. Running from 1954-1966, these files represent a vital piece of the intelligence picture of the global Cold War and decolonization at the end of Empire.
The Cabinet Office: CAB 56, CAB 121, CAB 176 & CAB 301
The material in these series dates from 1936-1974 and shows how intelligence matters were considered, analyzed, and processed through the Cabinet Office. Records from the Joint Intelligence Committee appear alongside Policy and Strategy files from the Special Secret Information Centre, and selected intelligence material from the Cabinet Secretary’s Miscellaneous Papers held in CAB 301.
The study of Intelligence and security casts light on international relations and politics, on social conditions and personal experiences in a time of conflict and shifting global alliances, on the running and dismantling of the Empire, and on the secret operations and planning of global conflicts. The politics of today are a direct result of the events of the twentieth century, and the depth and breadth of information gathered by British intelligence agencies revealed in this product, from British communists to African independence leaders and German Abwehr agents, allows scholars to follow the decisions and events that formed the world we live in.
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subjects covered
- Government
- Political Science & Diplomatic Studies
- Political Science
- Politics
- Twentieth Century Studies
- Social History
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