The Making of Bletchley Park and Signals Intelligence 1939–42

Abstract

The article argues that signals intelligence was an organizational accomplishment in the sense of requiring a) the establishment of an independent organization and b) that this organization combine cryptanalysis with intelligence analysis, traffic analysis and interception. This was not pre-ordained but the outcome of specific conflicts and decisions at Bletchley Park during the first three years of the Second World War which transformed the Government Code and Cypher School from a cryptanalytical bureau to a fully-fledged signals intelligence agency. Detailed archival evidence is presented in support of this claim.