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Espionage, propaganda and censorship
Spotlights on history - issues from the war
Alleged German 'war crimes'
The Armenian massacres
The antiwar movement
The blockade of Germany
Air raids
Demobilisation in Britain, 1918-20
Allied intervention in Russia, 1918-19


In pre-war Britain, the growing military threat of Germany created a climate in which popular novels about espionage thrived. Writers such as Glossary - opens new windowErskine Childers, author of The Riddle of the Sands (1903), and Glossary - opens new windowWilliam Le Queux depicted a sophisticated German intelligence network laying the foundations for an invasion of Britain.

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Journalistic fantasy

The truth was more prosaic. A small number of spies employed by the German navy were active in pre-war Britain. But between August 1911 and July 1914, the Glossary - opens new windowWar Office's counter-espionage department (known today as Glossary - opens new windowMI5) arrested just 10 suspects. Britain's own attempts to establish a spy network in Germany met with similarly little success.

The triumph - even in the highest government circles - of journalistic fantasy over mundane reality had immediate repercussions when war broke out in August 1914. An unprecedented 'spy mania' gripped Britain. Although 21 real German spies were arrested on 4 August, thousands of imaginary acts of espionage were reported to credulous police and military authorities.

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Homing pigeons, seen to be capable of carrying messages to the enemy, were killed. Thousands of false accounts of suspicious 'night-signalling', by which German spies might guide Glossary - opens new windowZeppelins or submarines towards their targets, were submitted. Le Queux's German Spies in England: An exposure, published to favourable reviews in February 1915, fabricated a system of German espionage that ranged from German prostitutes around Piccadilly Circus to 'naturalised' businessmen of the highest social standing. Such claims inevitably encouraged anti-German sentiments. On 13 May 1915, the Glossary - opens new windowAsquith government decided to intern all Glossary - opens new window'enemy aliens' residing in Britain for the duration of the war.

Similar, usually unfounded suspicions about German espionage activity in Britain were raised throughout the war. Enemy agents were variously accused of infecting cavalry horses with anthrax, starting fires in ports and posing as circus performers or commercial travellers to gain intelligence information.

Threat of German spies - opens new window
Threat of undercover
German spies (153k)

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Inept amateurs
Trial of Carl Hans Lody - opens new window
Trial of
Carl Hans Lody (137k)
Transcript & translation

In reality, the wartime operations of German espionage in Britain under Glossary - opens new windowGustav Steinhauer were limited and largely unsuccessful. Between August 1914 and September 1917, only 31 German spies were arrested on British soil, 19 of whom were sentenced to death and a further 10 imprisoned. Enemy spy activity thereafter was so negligible that no further espionage trials took place during the war.

Many of the men recruited by the Germans for intelligence operations were untrained and inept amateurs. Witness the case of Glossary - opens new windowCarl Hans Lody, the first wartime German spy to be executed in Britain, in November 1914. Viewed even by his captors as a decent and patriotic man, Lody left a trail of clues from his intelligence-gathering operations in Britain during August and September and was arrested in Ireland on 2 October. Most of the information that he sent to his superiors - such as the telegram on 4 September describing how Russian troops had apparently been seen marching from Aberdeen to the south of England - was useless.

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Successes with homing pigeons
British espionage and counter-espionage, though far from perfect, clearly outshone its German counterparts. MI5 - which had expanded rapidly from 19 members of staff in August 1914 to 844 by November 1918 - developed an effective system of cable and postal censorship that intercepted correspondence sent by a number of German spies. Aided by the Russian capture of the German navy's codebook from the wreck of the Glossary - opens new windowMagdeburg in October 1914, cryptographers working in Glossary - opens new windowRoom 40 at Admiralty headquarters in London successfully decoded wireless signals sent to and from the German naval fleet throughout the war.

Even on the Western Front, where War Office intelligence operations did not always run smoothly, there were great successes, most notably the use of homing pigeons to carry messages to and from operatives working behind enemy lines. Espionage thus played a small but significant role in the eventual Allied victory over Germany and its allies in 1918.

Secret writing on music score - opens new window
Music score with
'secret writing' (159k)

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Further research

The following references give an idea of the sources held by The National Archives on the subject of this chapter. These documents can be seen on site at The National Archives.

HO 45/10727/254753: Activity of enemy agents, 1914-16, including issue of homing pigeons.
KV 1/27: Forged American passport of German spy, 1916.
KV 1/41-48: Investigations into German espionage, 1914-18.
MEPO 3/2444: Various material on spy Mata Hari, 1915-17.
WO 94/103: Spies held in Tower of London during First World War, including those executed, 1914-18.
WO 141: Various individual cases of espionage, 1915-17.

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