MI6: The History of the Secret Intelligence Service 1909-1949, by Keith Jeffery, Bloomsbury RRP£30, 832 pages

A historian might pause when asked to write the history of an organisation that has destroyed most of its archive. When told he may not name any member who is still alive and must exclude the period on which its fame is largely based, then he could be forgiven for refusing the commission. Keith Jeffery, professor of history at Queen’s University, Belfast, accepted the challenge. As he writes in his introduction, such restrictions presented big disadvantages for Jeffery in trying to inject life into his history. What he has produced is a measured and scholarly work, but there is, nevertheless, life in it, too – and characters.

MI6’s job is to provide intelligence on “requirements” in the fields of national security and foreign, defence and economic policy. It is primarily a collection agency which is why, in its early days, it kept little of its raw material once it had been supplied to its customers. Its reliance on human sources – “agents” – who work in difficult and dangerous situations, and the fact that many MI6 officers work undercover to recruit and meet these sources, account for the service’s caution in this era of greater openness, and no doubt for the restrictions placed on this book. But it is a disappointment that the history stops at 1948, thereby excluding the cold war, the greatest period for espionage and counter-espionage in modern times.

In the absence of a substantial archive, research is largely from public records, collections of private papers, the published memoirs of those who dealt with the service and, very importantly for the early part of the book, the diary of Sir Mansfield Cumming, the first head of the service. After him, all successive heads of MI6 have been known as “C” and, following his habit, they write in green ink – though whether nowadays their e-mails are green, we do not know.

In 1909, Cumming was plucked out of the job of supervising Southampton boom defence to join Captain Vernon Kell in forming a secret service bureau. After a stuttering start, when nobody seemed to know what to do and Cumming complained to his bosses, “Surely we can not be expected to sit in the office month by month doing absolutely nothing”, it was resolved that Kell should undertake the whole of “home” work and Cumming should have charge of the “foreign”.

Initially, not much more thought than that seems to have been given to how best to organise Britain’s security and intelligence requirements. More than half the period covered by this book seems to have been spent by successive “C”s and assorted military and naval intelligence departments, Whitehall and the police arguing about who was in charge of whom, who should do what, how to get adequate funds for the job and whether the whole intelligence effort should be centralised or split. Reading about the constant bickering, one marvels that any intelligence work got done at all. Turf battles of more recent years pale when compared with these.

Cumming may have known nothing much about intelligence work when he was appointed, but he turned out to be made of sterling stuff and Jeffery has done a great job in bringing to life a man whom he clearly admires. Early on in the first world war, as the new foreign intelligence service faced its first challenge, Cumming suffered a serious accident when his son, driving him in France, crashed the car into a tree and was killed. Cumming was badly injured and had part of his leg amputated. He was soon back at work and his comment in his diary – “poor old Ally died” – epitomises a man guided by devotion to duty. After 14 years in the job, during which he negotiated his way round Whitehall and the military with charm and intelligence, working every day including Christmas, he died alone in his flat above the office, just before he was due to retire. He left a service with a worldwide remit to gather intelligence, but consisting of fewer than 200 people in 33 stations abroad.

His successor, Admiral Sir Hugh Sinclair, was very different. A noted bon vivant with a stormy private life and “an astonishing flow of forcible language”, this was a man whose expansionist ambitions – matched only by those of Sir Basil Thomson of Scotland Yard – led him to make a disastrous mistake for any intelligence chief: getting too close to politics, and moving from providing intelligence to advising on policy. Sinclair started to investigate communist subversion in Britain, running a group of agents known as “The Casuals”, and therefore crossing boundaries with the police and MI5. Eventually he was carpeted by the Home Office Permanent Under-Secretary’s Office and MI6 was stripped of domestic operations, which went to MI5, the division of responsibility that endures today.

Jeffery judges that by the beginning of the second world war, MI6, still learning how to satisfy the needs of its many customers, was held back by poor recruitment and remuneration and an almost total lack of operational training, as well as by the management gap between its tiny head office and its field stations. An over-emphasis on the threat from Bolshevism in the interwar years led to attention being directed far too late to German rearmament and the rise of the Nazis. But he debunks Hugh Trevor-Roper’s theory that MI6 was an irrelevancy to the Allied war effort and only survived the war at all because the Government Code & Cypher School came under its management and so “C” was able to get some of the credit for its valuable product. In fact, Sinclair foresaw the potential value of the codebreakers and started a discreet recruitment drive at the beginning of the war. There was a service legend that he purchased Bletchley Park out of his own pocket.

Sinclair died in office, just after the outbreak of war, and was succeeded by his deputy, Stewart Menzies, a workaholic in the Cumming mode who apparently took no break other than the occasional long weekend throughout the whole war. This history judges that MI6, starting from a low base, made a significant contribution to victory. The exploitation of pre-war liaison contacts, of Vichy sources and US relationships produced enormous intelligence benefits and MI6’s networks provided important intelligence on V-weapons and vitally informed the D-Day landings.

Jeffery concludes that the measure of MI6’s success in its first 40 years is its survival as a permanent and increasingly professional agency, by no means perfect and not without weaknesses and failures, but with a justified worldwide reputation. Readers will look forward to the history of the more recent 40 years, though perhaps more in hope than expectation.

Dame Stella Rimington was director-general of MI5 from 1992 to 1996. Her latest novel is ‘Present Danger’ (Quercus)

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