Late 1940s and 1950s

LATE 1940s AND 1950s

By 1948, the Soviets had undertaken systematic moves to bring central and eastern European countries under Communist control. These developments caused great concern in western Europe, as it was believed that the Soviets wished to expand their sphere of influence still further. As the then Attorney General Sir Hartley Shawcross put it on 13 March 1948, "the peoples of Western Europe ask themselves whose turn it will be next."

The British Prime Minster Clement Attlee announced on 16 March 1948 that Communists as well as Fascists were to be excluded from work deemed vital to the security of the State. Such individuals, Attlee declared, "would be prepared to endanger the security of the State in the interests of another Power."

A vetting system was established and the Service was given the task of supporting it. The measures undertaken following Attlee's announcement made a vital contribution to the safeguarding of national security. In a sense, this was not a new development; as far back as the First World War, the "preventive" security branches were at least as large and important as the counter-espionage branch. The provision of security coordination and advice is still a central part of the Service's work.

Internal reforms

The remit of the Security Service was reformed and clarified in 1952 by Winston Churchill, in his second term as Prime Minister. He delegated his personal responsibility for the Security Service to his Home Secretary, Sir David Maxwell-Fyfe. The tasks of the Service and the roles of the Director General were set out by Maxwell-Fyfe in a directive which provided the basis for the Service's work until 1989, when the Security Service Act placed it on a statutory footing for the first time (see "Statutory basis").

By the early 1950s, staff numbers had increased to about 850. This included some 40 Security Liaison Officers overseas, who provided advice and assistance to governments in the Commonwealth and Colonies.

Infiltration and subversion

The United Kingdom was