Major MI5 release from UK National Archives

The UK National Archives have this week released a tranche of over 100 previously secret files on the British Security Service, MI5. The new documents, which cover a period from the service’s inception in 1909 up to the mid-1970s, are available online here.

The volume of coverage suggests there’s been a pretty substantial press preview, but it may take a while for the full significance of the release to become clear.

According to historian Chris Smith, ‘there is so much material in the files dropped by the National Archives today that it will take months if not years to digest it all.’

Nevertheless, the release has already aroused some informed comment. UK intelligence expert Dr. Dan Lomas has bemoaned a focus on the perenially well-trodden ground of the Cambridge spy ring. His fellow historian Rory Cormac suggests there is still one major question the files could usefully answer on Cambridge spy Anthony Blunt: ‘what, if anything, did Blunt have to do with intelligence post-1964 whilst still at the palace?’

Journalist Michael Smith reports that not everything in the release is entirely new. He previously published an MI5 guide to physical surveillance in his book The Spying Game, having found a copy in the archives of Russia’s foreign intelligence service, the SVR.

For researchers, the blog by the National Archives’ Mark Dunton is a good place to start as it puts some file references to the themes emerging in the media. Below is a sampling of some of those stories.

14 January

Sanchia Berg, Queen not officially told for years about Palace spy, MI5 papers reveal, BBC News.

Bill Goodwin, Many are called, but few are chosen: Secrets of MI5 watchers revealed, Computer Weekly.

Richard Norton-Taylor, Labour leader praised MI5 for spying on trade union, Declassified UK, 14 January 2025.

MI5 pushed to list FBI director J Edgar Hoover as ‘honorary knight’, Financial Times.

Caroline Davies, MI5 files suggest queen was not briefed on spy in royal household for nine years, The Guardian.

Rebecca Camber, Dirk Bogarde was a 'practising homosexual' and the KGB targeted him for entrapment, declassified files reveal, MailOnline.

Michael Holden, Secret UK files detailing confessions of Cambridge Five spies released, Reuters.

Queen kept in dark over palace traitor Anthony Blunt, declassified documents reveal, Sky News.

Trevor Barnes, Elizabeth II ‘very calm’ when warned about Russian spy Anthony Blunt, newly released MI5 documents show, Standard.

Fiona Parker, Revealed: MI5’s 17-page guide to being a spy, Telegraph.

Ben Macintyre, Kim Philby: spy’s final secrets revealed in archives, Times.