ABSTRACT
At the beginning of the Second World War SIS maintained their overseas presence through a chain of stations vulnerably co-located with Passport Control Offices, and through a separate network of agents – the ‘Z’ network – operating under commercial cover. During the 1930s, with very limited resources, they were confronted by the formidable task of gathering intelligence on both the Stalinist Soviet Union and national socialist Germany, and it is generally accepted that their activities were more effectively oriented towards the former than the latter. In the years preceding the outbreak of hostilities SIS incurred mounting criticism from the Armed Services because of their failure to obtain much good-quality information on German military preparations. By the time Germany invaded France and the Low Countries in 1940 most of the Passport Control Offices in western and central Europe had been evacuated, and the ‘Z’ network had been fatally compromised following the capture of two leading SIS field officers by the German Security Service at Venlo, Holland, in November 1939.1
With no contingency plans for the German occupation, SIS’s European activities became largely confined to stations on neutral soil, such as Stockholm, Lisbon and Berne, or to more peripheral capitals like Istanbul and Tangiers.2 SIS otherwise located very few agents in occupied countries and instead relied heavily on networks established by London-based intelligence services-in-exile, such as the Czech, Norwegian, Polish, Dutch and French secret services.3 They also began the War with only a minimal presence in British-controlled areas of the Middle East: such territories had normally been considered the responsibility of the Security Service (MI5) and its military intelligence colleagues on the local commander-in-chief’s staff.4 In July 1940 SIS lost Section D, a directorate responsible for irregular warfare in enemy territories, when Churchill established a new and entirely separate organization to undertake sabotage and subversion in German-occupied Europe – SOE. And even SIS’s most notable coup, the successful decryption of German signals sent via the Enigma cipher machine, was at first devalued because the military authorities instinctively doubted the reliability of what they presumed to be just another conventional (and therefore suspect) secret intelligence source.5
