London, UK
Reuters
Britain’s GCHQ spy agency celebrated the 80th anniversary of Colossus on Thursday, putting the spotlight on a code-breaking computer which helped defeat Hitler’s Germany and was so significant it was kept secret for decades.
In 1944, Colossus, the world’s first digital computer, decoded German messages which convinced Allied forces their year-long plan to deceive Hitler over the location of the invasion had been successful, giving D-Day the go-ahead.
A general view of Colossus, the codebreaking computer, used at Bletchley Park during World War II in this handout image obtained by Reuters on 17th January, 2024. PICTURE: Crown Copyright reproduced by kind permissions of Director GCHQ/ Handout via Reuters
In the run-up to the landings on the French coast, a turning point in World War II, Colossus played a pivotal role behind the scenes and is credited by many experts with shortening the war.
A two-metre tall frame of switches and plugs draped in wires, Colossus tapped and pulsed paper tape, using 2,500 valves to process information faster than ever before, cutting the time it took to decode messages to hours from weeks.
But it was only in the early 2000s that its existence was revealed, and now 80 years on, Britain’s GCHQ signals intelligence agency has released a series of never-before-seen images and sounds to mark its anniversary.
“Technological innovation has always been at the centre of our work here at GCHQ, and Colossus is a perfect example of how our staff keep us at the forefront of new technology – even when we can’t talk about it,” GCHQ’s director Anne Keast-Butler said in a statement.
Colossus, which was still being used by the spy agency in the early 1960s, was developed by Tommy Flowers. It followed the “bombe” codebreaker machine, Alan Turing’s electro-mechanical device which deciphered Germany’s naval Enigma code from 1940 onwards, a breakthrough dramatised in the 2014 thriller The Imitation Game.
The new images released on Thursday include a blueprint of Colossus and a photograph of Women’s Royal Naval Service workers operating it. Such was the secrecy around the machine, many of the engineers and staff working on it did not know what it was.
The first Colossus was delivered to Bletchley Park, then the home of the top secret Government Code and Cypher School, on 18th January, 1944. By the war’s end there were 10 of the machines operating. The unit was renamed in 1946 as the Government Communications Headquarters (GCHQ), a Cheltenham-based agency that eavesdrops on the world to protect British security.
