Peshawari dead in the middle of the courtroom. The head of Special Branch in London, Basil Thomson, commented:
In the Western [United] States such incidents do not disturb the presence of mind of Assize Court officials: the deputy sheriff whipped an automatic from his pocket, and from his elevated place at the back of the court, aiming above and between intervening heads, shot the murderer dead.18
The Indian National Congress – the political body that would later become the main vehicle for anti-colonial nationalism in India – does not seem to have attracted any significant attention from MI5 or any other section of the British intelligence community during the First World War. This was partly because Congress had no significant wartime German connection, but also because before 1914 it was little more than a middle-class debating society that met only sporadically. There was nothing to suggest that it would emerge from the war as a mass movement that would become a focus for resistance to the British Raj. The main transformation of Congress’s fortunes would be due to Mohandas Karamchand ‘Mahatma’ Gandhi, an English-educated barrister of Inner Temple, who more than anyone else would set in process the downfall of the British empire in India a generation later. Nevertheless, in retrospect it is clear that in the pre-war and wartime years, MI5 and British intelligence authorities in India showed a remarkable lack of interest in Gandhi. When he returned in 1915 to India from South Africa, where he developed the technique of satyagraha, or passive resistance, which he later used against the Raj, the Department of Criminal Intelligence in Delhi described him as ‘neither an anarchist nor a revolutionary’, but just as a ‘troublesome agitator whose enthusiasm had led him frequently to overstep the limits of South African laws relating to Asiatics’.19
Reflecting the worldwide nature of the war, that same year, 1915, the British Chiefs of Staff instructed MI5 to establish a department to deal with German-sponsored subversion in the British empire. This new department, D-Branch in MI5, led by an officer called Frank Hall, expanded rapidly, so that by 1917 it had nineteen full-time officers. For cover, D-Branch used the name ‘Special Central Intelligence Bureau’ when communicating with colonial and Commonwealth governments. According to a post-war report compiled on D-Branch, its responsibilities included undertaking visa checks on individuals travelling in the empire and providing colonial governments with information on known and suspected German agents. By 1916 D-Branch was in touch with ‘the authorities responsible for counter-espionage in almost every one of the colonies’. However, during the war MI5 did not actually station officers in British colonies or other dependent territories overseas. Instead, it operated as a ‘clearing house’ for security intelligence on German espionage and subversion by maintaining direct personal contacts with a number of colonial police forces, known as its ‘links’, and consolidating all the information it received from those links across the empire into a single registry, which contained around 45,000 records in 1917. By the end of the war MI5 could justifiably boast that it presided over a unique, empire-wide index of security intelligence information. One of the clearest manifestations of its dramatically increased responsibilities was its famous ‘Black Lists’ of German agents, which it circulated to all colonial and Commonwealth governments. These grew from a single volume in 1914 to a weighty twenty-one volumes in 1918, which included 13,524 names.20
The most famous example of German attempts to sponsor subversion in the British empire involved British counter-measures orchestrated by the now-legendary figure T.E. Lawrence, ‘Lawrence of Arabia’ – Oxford historian, archaeologist, cartographer, linguist, intelligence officer and expert guerrilla fighter. Lawrence and his colleagues, a group of self-proclaimed ‘intrusives’, established the so-called Arab Bureau in Cairo in 1914, which pioneered the use of guerrilla warfare against Turkish forces fighting on the side of Germany and the Central Powers in Arabia. In many ways the efforts of Lawrence and British forces in the Middle East during the First World War represent the first modern intelligence war: Lawrence’s forces combined intelligence gained from human agents with intelligence from signals radio intercepts, processes which are now known as human intelligence (HUMINT) and signals intelligence (SIGINT) respectively. The use of aerial reconnaissance, now known as image intelligence (IMINT), was also pioneered by the Royal Flying Corps in the clear skies over Arabia.21
The most important success of the Arab Bureau in its four-year wartime existence was to convince the War Office in London not to send an expeditionary force to Arabia. Lawrence and others in the Arab Bureau argued that a permanent British force landed in the Hejaz, the rocky province bordering the Red Sea, would inevitably be regarded by Arabs as an invading Christian, ‘crusader’ force – with disastrous consequences. Instead, the Arab Bureau insisted that the British should forge an alliance with the local Hashemite dynasty, who could take primary responsibility for fighting the Central Powers in Arabia, with the British providing assistance through intelligence and irregular warfare. This is precisely what occurred. British forces, led by Lawrence, collaborated with the Sharif of Mecca, Hussein bin Ali – who claimed to trace his descent back to Mohammed and Adam – and waged a series of spectacularly successful guerrilla attacks on Turkish and German forces in the Sinai Peninsula, conducting diversionary raids on railways and assaults on isolated garrisons in the Hejaz, through Aqaba to Amman and Damascus. In his famous self-dramatising account of his wartime exploits, Seven Pillars of Wisdom, Lawrence emphasised that intelligence-gathering was the key to successful irregular warfare: ‘The first line of guerrilla warfare,’ he wrote, ‘is accurate intelligence.’ Lawrence’s wartime mission was to divert Turkish forces from Palestine to protect the Hejaz railway. Assisted by Lawrence’s diversionary actions in the Hejaz, the leader of the Egyptian Expeditionary Force, General Edmund Allenby, won successive victories in Gaza and Beersheba, which ultimately led to the capture of the city of Jerusalem in December 1917. Allenby was joined by Lawrence in triumphantly entering the Holy City on foot – the first Christian soldiers to capture the city since the time of the Crusades.22
As well as attempting to incite subversion against the British in India and the Middle East, the German military also sponsored unrest in one of Britain’s closest imperial possessions: Ireland. In fact, one of the most notorious cases that British intelligence was involved with in the entire First World War related to German attempts to forge an alliance with dissident Irish republicans. During the war, the signals department of the British Admiralty, codenamed ‘Room 40’, led by Reginald ‘Blinker’ Hall, grew in importance and size, and successfully intercepted and read many German communications. As with the rest of the British intelligence community, the war transformed the scale and nature of the British SIGINT, institutionalising code-breaking in ways that had not previously existed in Britain. One of the most notorious wartime German communications intercepted and circulated by Room 40 was the so-called ‘Zimmermann telegram’ of January 1917, in which the German Foreign Minister, Arthur Zimmermann, offered the Mexican government the chance to retake lost territories in the United States, including land in Texas, Arizona and New Mexico, if it declared war on the United States. Although the Zimmermann telegram is commonly known to be one of the causes of the US government’s entry into the war, the role that Room 40 played in the episode is still generally not properly appreciated in most histories of the First World War, despite having been discussed by intelligence historians for over thirty years: Room 40 intercepted the notorious telegram and passed it on to US authorities, who then publicly exposed it, while keeping secret the role of British code-breakers.23
In the two years after outbreak of war in 1914, Room 40 code-breakers decrypted at least thirty-two German cables relating to Irish nationalists. The most important related to the ‘Easter Rising’ of April 1916, and Germany’s support of an exiled Irish nationalist, Sir Roger Casement, to help carry out the uprising in Dublin. Room 40’s decryption efforts gave the British government foreknowledge of the uprising, and provided exact knowledge of Germany’s arms supplies to Ireland. On information provided by Room 40, in April 1916 the Royal Navy intercepted the U-boat carrying Casement to Ireland before he could carry out his mission. Casement was ultimately executed by the British in Dublin in August 1916. During his incarceration he begged the British authorities to allow him to communicate with the leaders of the uprising, and warn them to abandon their plans. However, it seems doubtful that even if he had made such an intervention it would have prevented the council of the Irish Republican Brotherhood from proceeding. Furthermore,