Room 40 at the Admiralty

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Room 40 at the Admiralty

The First Bletchley Park: This incredible image taken in June 1919 shows World War One codebreakers – including Major Malcolm Hay (back left) in their secret office in London. The organisation, known as Room 40, had a pivotal role in bringing the Great War to an end

From 1914 the conflict at sea fell into two, almost distinct, parts: the surface engagements of the bigger ships, sometimes in line ahead, pounding each other with their heavy guns; and that of a secret U-boat war of sudden and unexpected torpedo attacks. This last part had political as well as economic effects. The Royal Navy’s strategy was to use their big guns to enforce a total economic blockade of ships supplying Germany and her allies. The North Sea was to be a war zone and boarding parties from the Royal Navy ships made stringent checks on neutral shipping for any goods meant for a German port. It was a brutal, effective and probably illegal weapon, in response to which Norway, Sweden, the USA, as well as other countries, made loud protests about the contravention of international law. The British did not acknowledge their protest so the Royal Navy maintained a very effective blockade with a relatively small number of warships because of the good intelligence from wireless intercepts about German shipping movements. In response, German U-boats were ordered to sink any ships found in British waters in an act of unrestricted warfare. A savage battle was fought in the First World War, as well as the Second World War, as the two opponents tried to strangle each other to death. The stakes were that the population of the loser would starve. The Royal Navy was well equipped to combat surface ships, but was woefully unprepared for the U-boat threat; however, signals intelligence was going to play a crucial part in the great sea battle that lay ahead.

The Admiralty had fitted wireless telegraphy in all its major vessels by the beginning of the First World War, but was still unprepared for the signals intelligence battle in which they were about to become engaged. They had some hints of what part wireless telegraphy might play from their experience in observing the use of wireless telegraphy in 1904 during the Russo-Japanese War. An ageing coal-fired Imperial Russian Fleet left their base at St Petersburg to undertake a mammoth trip through the Suez Canal and into South East Asian waters to finally arrive in the Sea of Japan to engage the Imperial Japanese Navy. The British, and indeed the world, watched the slow progress of Russia’s fleet by monitoring its wireless communications during the course of their long journey. The W/T specialists on board the Royal Navy ship HMS Diana, which shadowed the fleet, commented on the poor standard of transmission and encoding of messages coming from the cumbersome Russian fleet as it chugged halfway around the world to confront the Japanese. The Russian Imperial Fleet engaged the Japanese battleships and was almost totally destroyed, distress calls transmitted by sinking battleships filling the airwaves. Russia’s defeat was reported back by wireless to the Admiralty in London, but the lessons of the extended exercise in the use or misuse of wireless telegraphy were ignored. The British Admiralty had no signals intercept service or plan to create one in 1914 as war started, but luck was on their side.

Within days of the declaration of war in August 1914, the Admiralty’s recently appointed Director of Intelligence Rear Admiral Henry Oliver was being given copies of intercepted German wireless transmissions in code that he was unable to read. Winston Churchill, who was First Lord of the Admiralty, and the soon to be appointed First Sea Lord Admiral John (Jackie) Fisher, asked Oliver to set up a wireless intercept service. The Admiralty allocated Room 40 in their Old Building to house this new service. Room 40 would be the title of a signals intelligence bureau that would achieve extraordinary things, first for Britain’s war at sea and later as an intelligence centre of wider dimensions. Oliver needed a director for the embryonic intercept service so he turned to his old friend Sir Alfred Ewing, who was Director of Naval Education, and over lunch at the United Services Club, now the Institute of Directors, he offered him the job. Ewing had been a great success at educating navy personnel and had received a knighthood; in addition, Oliver knew that he had an academic interest in codes and ciphers. Ewing, immaculately dressed and conscious of his position and dignity, was an inspired choice for the job with more than his share of luck in its success. Ewing’s first move was to review what there was in coding and ciphering expertise in the archives of The British Library, the General Post Office, Lloyds and other repositories of literature and experience on the subject. His conclusion was that he needed a multi-talented team to help him in the task whose shape was beginning to emerge.

German wireless transmission intercepts were coming in thick and fast from radio listening stations, or ‘Y’ stations as they came to be known, that began to be installed all along England and Scotland’s east coasts. Piles of German transmissions in code and a few in plain text from new ‘Y’ stations were gathering at the Admiralty, in addition to other contributions from radio amateurs who began to play their part in intercepting German messages. Ewing’s ever-increasing supply of messages in cipher needed code breakers to work on them, but also people who could understand the purport of a message in naval terms and practice. The intercepts were all in German, too, so the team that Ewing needed to recruit had to contain talented cryptanalysts, naval officers and translators to create a bureau that would help to shape the war to come.

In the early days, Room 40 in the Admiralty Buildings in Whitehall began co-operation with the Army at the War Office just across the road. The army did not have the flying start in putting together a decryption team that the navy was enjoying, but progress with interception was shared. Some decryptions of German coded messages began to emerge as Ewing’s small but growing team began to bed down in their task. This co-operation did not last long, however, as Room 40 began to prove itself the better bureau of the two and was rather pleased to show it. In Germany at the same time there was no initiative to create an intercept service and, when a German signals intelligence team was finally inaugurated, it proved trivial compared to the British effort. Even Room 40 was not without its shortcomings, however. Intelligence has several aspects to it, each of which needs to work in balance with the others. The accurate interception of a coded transmission was the first stage. Decoding it was next; a translation was needed, which required a knowledge of German marine terminology and practice to make sense of the message. From those fragments of information, and maybe others collected earlier, an evaluator’s skill was needed to build a coherent summary of intelligence for the field commander. These evaluations could support and guide life and death decisions for those directing the ships or ground forces in the face of the enemy.

The directors of intelligence had to decide to whom they should show this precious knowledge of the enemy. Cast the distribution list too narrowly, as Hitler did, and you limit the use of valuable intelligence, but cast it too widely and the risk of a disaster in the shape of a leak could betray your sources to the enemy who would promptly close them down. It was a difficult balance between too open-handed a distribution of your intelligence and paranoia about the enemy’s spies that are always a risk to your secret sources and plans. Room 40 as a bureau had limited its effectiveness by restricting its agenda to acting largely as an interception and decoding role rather than a wider intelligence centre into which it would evolve later in the war. Oliver and Ewing had built up an extraordinarily effective decoding facility, but would play what intelligence cards they had very close to their chests. This meant that any useful intelligence their cryptanalysts had generated had a more limited effect than it could have done. Later in the war, Room 40’s capability came into its own as a fully effective, intelligence-gathering, evaluation and exploitation organisation under the inspired leadership of Admiral ‘Blinker’ Hall. He was not only a superb spymaster but a great judge of men; one of his many lieutenants, Commander Alastair Denniston RN, served his signals intelligence apprenticeship under Hall and was to make his mark in intelligence later on.

To meet the need of the unsolved coded intercepts the Admiralty began by recruiting bright young men and their tutors from the universities for cryptanalysis and linguistic work in the Room 40 team. The foundation of Britain’s signals intelligence bureau and their cryptanalysis skills was being laid by Ewing’s growing team; its effectiveness would last for half a century or more. Sadly, a damaging quarrel between the War Office, or MI 1B as it was designated, and the Admiralty across the road in Whitehall was not resolved until 1915. Such squabbles are not an unknown phenomenon among security services of virtually all nations, even up to the present day. The ‘spat’ limited the development of the army’s military code breaking unit in the precious months during the opening phases of the war. The main reason for the row seemed to be that the ‘Y’ stations intercepting enemy signals were gathering a mix of messages of both naval and military interest, so the War Office and the Admiralty agreed to a guarded co-operation. This arrangement broke down as a result of what seems an immature competition between the two services, probably because Room 40 at the Admiralty was making better progress in decoding intercepted messages than the War Office – and flaunted it. The Admiralty was preparing to go it alone in their signals intelligence war.

Wireless telegraphy was a fairly recent invention in 1914, but it had been made a standard installation in all major Royal Navy ships, as well as those of the fast expanding Imperial German Navy. Telegraphy was widely accepted and practiced by sea goers as it could act as a lifeline, helping them to survive the dangers of the sea, but it was just about to become an effective weapon of offence as well.

Germany was loath to risk her navy against a larger British fleet in a major action, so they decided on a strategy of attrition by trying to catch smaller detachments of the British warships in short, sharp actions. Penetration of German naval codes and ciphers by the British using the new technology helped them to counter this strategy. Deception in signals transmissions became a widely used practice by both the British and German navies, often in innovative ways. One aspect of signals security for ships at sea was to disguise the recipient of a radio message, so a common ruse among German transmitters was to direct a message from one coastal station to another rather than to the ship at sea for which it was really intended. The vessel would ‘overhear’ the message and act upon it; this was the beginning of a wireless-based game of hide and seek played by intercept services to help win or lose the war at sea.

Ewing needed cryptographers urgently so the first place that he looked was within the Royal Navy itself, with staff members of the colleges at Dartmouth and Osborne the first to be interviewed. One candidate was Alastair Denniston, who was teaching German at Osborne. He was offered an appointment which was assumed by all to be a short-term one during the school holidays that he was then enjoying. No one envisaged that the war would last for several years and that cryptology would prove a life-long career for Alastair. He became a major figure in Britain’s long chronicle of cryptology and intelligence spanning almost half a century and two world wars. Ewing recruited a disparate team of characters who came from many walks of life, creating a mixed bag of extraordinarily cerebral linguists and naval experts in his team. Room 40 would prove far too small for the fast growing band of decoders, but it did have the advantage of being situated in the Admiralty Building within a few moments’ walk of Churchill’s and Fisher’s offices. Churchill decided that there should be some ground rules for the staff, and his directions, written on a single page of Admiralty notepaper and dated 8 November 1914, is still in Britain’s archives. It is headed ‘Exclusively Secret’ and addressed to COS (Chief of Staff, Admiral Oliver) and D of Educt- (Director of Education, which is a position Sir Alfred Ewing still retained) and read:

An officer of the War Staff, preferably from the ID (Intelligence Division) should be selected to study all the decoded intercepts, not only current but past, to compare them continually with what actually took place in order to penetrate the German mind and movements and make reports. All these intercepts are to be written in a locked book with their decoded, and all other copies are to be collected and burnt. All new messages are to be entered in the book, and the book is only to be handled under the direction of the COS.

The officer selected is for the present to do no other work.

I shall be obliged if Sir Alfred Ewing will associate himself continuously with this work.

The order has the initial WSC in red ink, the date 8/11 and the counter-signature of Admiral Fisher which was an F in green ink.

Paranoia was working fine in the Admiralty.

Forschungsmitarbeiter Mitch Williamson is a technical writer with an interest in military and naval affairs. He has published articles in Cross & Cockade International and Wartime magazines. He was research associate for the Bio-history Cross in the Sky, a book about Charles ‘Moth’ Eaton’s career, in collaboration with the flier’s son, Dr Charles S. Eaton. He also assisted in picture research for John Burton’s Fortnight of Infamy. Mitch is now publishing on the WWW various specialist websites combined with custom website design work. He enjoys working and supporting his local C3 Church. “Curate and Compile“
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