Subject

British intelligence and security organisation, responsible for providing signals intelligence and information assurance to the government and armed forces. Originally established after WWI as the Government Code and Cypher School (GC&CS) in Watergate House. During WWII it was relocated to Bletchley Park, where it was famed for breaking the German enigma codes. Renamed Government Communications Headquarters in 1952.

During WW1 the Army and Navy had separate signals intelligence agencies: MI1b and Room 40, respectively. Then, Fortune tells: "Established on November 1, 1919, as a peacetime code-breaking unit made up from staff from the Royal Navy and War Office, GCHQ was first known as the Government Code & Cypher School (GC&CS). ... During WWII, its staff operated covertly from Bletchley Park in Bedfordshire... Palmer Street {2-14} - known as station UKC1000 - came into operation in the Spring of 1953 to serve as a central London spy hub, shortly after GCHQ moved its main headquarters from the London suburb of Eastcote to the sleepy, rural surroundings of Cheltenham in Gloucestershire. ... "