For most of the twentieth century, Britain’s foreign intelligence service officially did not exist. Then, for its centenary, MI6 did something no spy agency had done before: it handed its own secret files to a historian and let him publish. The result — MI6: The History of the Secret Intelligence Service 1909–1949 by Keith Jeffery — remains the closest thing the reading public will ever get to the real, declassified birth of British espionage. A preloved copy recently surfaced (and quickly sold) through the Indian rare-book seller Old Book Depot on Instagram — a fitting reminder that this once-classified history is now a book hunters trade like treasure.
An authorized history — from the files themselves
Keith Jeffery, Professor of British History at Queen’s University Belfast, was appointed in 2005 to write the first official history of the Secret Intelligence Service. What made the project extraordinary was the access: Jeffery worked from SIS’s own archives — operational files, internal correspondence and records that had never been opened to any outsider — covering the service’s first four decades. Published by Bloomsbury in September 2010, the book runs to more than 800 pages, carries a foreword by the then-serving Chief of SIS, Sir John Sawers, and its copyright is held not by the author but by the Crown. In the United States it appeared under the title The Secret History of MI6.
What the book covers
The story opens in 1909, when Royal Navy officer Mansfield Cumming became the founding chief of the new Secret Service Bureau’s foreign arm — the original “C”, a title every SIS chief still carries, signing in green ink as Cumming did. From that one-man beginning, Jeffery traces:
- The First World War: improvised agent networks in occupied Europe, the race to map German naval plans, and the service’s baptism by fire against Bolshevik Russia.
- The interwar years: a tiny, underfunded service watching fascism and communism rise, running agents from passport offices and listening posts across the continent.
- The Second World War: SIS’s defining era — continental networks rebuilt after catastrophic early losses, the alliance with America’s OSS (ancestor of the CIA), and intelligence battles that ran parallel to the military war.
- The early Cold War (1945–1949): the pivot to the Soviet target, the first joint operations with the newborn CIA, and the service’s shape settling into the institution the world now knows as MI6.
Why it stops at 1949
Readers sometimes ask why an “official history” ends in 1949, decades before the modern era. The answer is the archive itself: SIS opened its files only up to that line. Everything after — the Cambridge spies’ full fallout, the Cold War’s hottest years, the post-Cold-War service — remains classified, and no second authorized volume covering it has appeared. What Jeffery could use, he used in full: the book is dense with the service’s internal machinery — budgets, bureaucracies, rivalries and failures — not just its triumphs, which is precisely what gives it credibility.
Part of a remarkable publishing moment
Jeffery’s volume landed in the middle of an unprecedented opening of Britain’s secret state. Christopher Andrew’s authorized history of MI5, The Defence of the Realm, had appeared in 2009, and Richard Aldrich’s GCHQ followed in 2010. Together they marked the long road from the decades when SIS was not even avowed — its existence was only formally acknowledged in law by the Intelligence Services Act of 1994 — to an era in which the service could celebrate its centenary in print.
Who should read it
This is not a thriller, and it does not pretend to be: it is a serious, archive-based history, at times deliberately unglamorous about the paperwork of espionage. But for anyone who wants to know how the real service behind a century of spy fiction actually began — the real “C”, the real networks, the real compromises of two world wars — there is still nothing else like it, because there is still no other book written from inside the files. Copies surface regularly in the second-hand trade (the Old Book Depot copy sold fast), and the paperback remains in print.
Book details
- Title: MI6: The History of the Secret Intelligence Service 1909–1949 (US title: The Secret History of MI6)
- Author: Keith Jeffery (1952–2016), Professor of British History, Queen’s University Belfast
- Publisher: Bloomsbury, September 2010 — ISBN 978-0-7475-9183-2
- Length: 832 pages (hardcover)
- Status: The first — and still the only — authorized history of SIS, written with access to its classified archives
FAQ
Is this an official MI6 book?
Yes. SIS commissioned it for the service’s centenary, Jeffery worked from the agency’s own archives, the serving Chief wrote the foreword, and the Crown holds the copyright. It is an authorized history — independent scholarship, but with unprecedented access.
Does it cover James Bond-era MI6 or the Cold War?
Only the very beginning of the Cold War: the book ends in 1949 because SIS opened its archives only up to that year. The later Cold War remains classified.
Is it readable for non-historians?
Yes, with patience: it is a substantial, detailed history rather than a spy thriller, but the two world wars sections in particular read as a gripping account of how modern espionage was invented on the fly.
The verdict
Every spy library has one anchor book, and for the real MI6 this is it: the service’s own files, opened once, for the first forty years. Whether you find it new in paperback or preloved through a bookseller’s Instagram post, MI6: The History of the Secret Intelligence Service 1909–1949 is the rare “secret history” that actually earned the name.
