Alastair Denniston: Code-breaking From Room 40 to Berkeley Street and the Birth of GCHQ

Some of the individuals who played key roles in the success of Bletchley Park in reading the secret communications of Britain’s enemies during the Second World War have become well-known figures. However, the man who created and led the organization based there, from its inception in 1919 until 1942, has, surprisingly, been overlooked – until now. In 1914 Alastair Denniston, who had been teaching French and German at Osborne Royal Navy College, was one of the first recruits into the Admiral...