Gale Debuts New Digital Archive Series on British Intelligence

The first module of Gale's new Declassified Documents Online: Twentieth-Century British Intelligence explores the history of British Intelligence during an era of global conflict and careful diplomacy, of the rise and fall of political extremes, of great strides in technology and of vast change in the everyday lives of people around the world.

Gale, a Cengage company, introduced the first module of its new Declassified Documents Online: Twentieth-Century British Intelligence series. Declassified Documents Online: Twentieth-Century British Intelligence, An Intelligence Empire brings together previously classified documents from The UK National Archives (although some MI5 files were declassified in 2017 and 2019) that offer new viewpoints on the machinery of British intelligence, decolonization and global policy and strategy, including important insight into international politics and diplomacy in the 20th century. Available on the Gale Primary Sources platform, this never-before-digitized collection gives scholars and researchers access to thousands of top secret files that provide historical context on the history of British intelligence. Now researchers can make comparisons and connections, enabling greater understanding of the historical impact Britain's intelligence agencies have had on the world today. Read Gale's blog about this new archive.

The breadth and depth of the archive makes it a major source for 20th century teaching and learning.

"Looking back on the 20th century from an intelligence perspective can help us understand how the geopolitics of the 21st century developed, and how the world as we know it came to be," said Seth Cayley, vice president of Gale Primary Sources. "By bringing together material from across security and intelligence branches, Declassified Documents Online: Twentieth-Century British Intelligence, An Intelligence Empire will help scholars and researchers delve into the role of intelligence in theory and in practice, while newly declassified pieces offer possibilities of new research and new readings of historical events."

An Intelligence Empire provides insight into the interests and activities of the British Empire, its allies and enemies through highly secret documents, from the precursors to Room 40 in WWI and WWII networks of subterfuge and resistance, to the geopolitics of the Cold War and beyond.

This vast collection includes top-level memoranda, registered files, correspondence and policy documents from British government agencies and committees working within intelligence and security, including MI5, the Ministry of Defence and the Joint Intelligence Committee. The breadth and depth of the archive makes it a major source for 20th century teaching and learning.

An Intelligence Empire brings together files from five departments:

  • The Security Service (MI5): KV 2, KV 3 & KV 4: contains personal, subject and policy files dating from 1917-1978. 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, while KV 3 contains subject files on espionage activities of groups or other intelligence organizations, including the only subject file 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 20th century, and include defense records on the Falklands, the Middle East, UFO incidents and details of Soviet weapon systems.
  • The Special Operations Executive: HS 7 & HS 8: 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 and 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.

New & Exclusive Search Capabilities!

With the release of this archive comes a host of new search capabilities for teaching and researching that are exclusive to the series:

  • Browse Collection: available from each collection, this feature enables researchers to browse a complete list of files in the order they were arranged by The National Archives. This not only provides a 'bird's-eye view,' of the entire collection, but is also a quick and easy access point to specific documents. This feature is also an effective teaching tool that instructors can use to teach students how an archival collection is organized and how to navigate it for researching.
  • Manuscript Number Sort Search: users can sort their search results list by manuscript number, which is the order a collection was arranged in by the source library. This recreates/simulates the experience of working through the physical collection in the source library.
  • Special Advanced Search Options: gives users the ability to limit a search by: 1). creation date, 2). declassified date, 3). government department, 4). classification level and 5). regional focus. These search options were built to support the specialized nature of the government documents in this archive, enabling researchers to differentiate between when a document was created versus when it was declassified by the U.K. government.

The Declassified Documents Online: Twentieth-Century British Intelligence series is available on the Gale Primary Sources platform, enabling cross-archival searching to help users make new connections across topics. For those looking to explore even deeper insights, the series is also available through the Gale Digital Scholar Lab. This allows researchers to apply natural language processing tools to raw text data (OCR) from the collections or Gale Primary Sources archives and perform textual analysis on large corpora of historical texts. Now researchers can analyze and explore historical text more interactively, generating new research insights and content sets not previously possible.

To request a trial, visit the Declassified Documents Online: Twentieth-Century British Intelligence webpage.

About Cengage and Gale
Cengage, an education technology company serving millions of learners in 165 countries, advances the way students learn through quality, digital experiences. The company currently serves the K-12, higher education, professional, library, English language teaching and workforce training markets worldwide. Gale, a Cengage company, provides libraries with original and curated content, as well as the modern research tools and technology that are crucial in connecting libraries to learning, and learners to libraries. For more than 60 years, Gale has partnered with libraries around the world to empower the discovery of knowledge and insights – where, when and how people need it. Gale has 500 employees globally with its main operations in Farmington Hills, Michigan. For more information, please visit

Media Contact: Kayla Siefker, Gale, a Cengage company, +1 248-915-9624,