The Codebreakers: Who Worked at Bletchley Park During World War Two?

History Hit Podcast

3 mins

20 Sep 2018

This article is an edited transcript of Bletchley Park: The Home of Codebreakers on Dan Snow’s History Hit, first broadcast 24 January 2017. You can listen to the full episode below or to the full podcast for free on Acast.

By the end of the Second World War in 1945 nearly 10,000 people worked at Bletchley Park, an enormous increase on the 130-strong staff that composed the Government Code and Cypher School in 1939.

In many ways it was one of the most remarkable groups ever assembled.  

How Bletchley utilised a huge team to industrialise codebreaking

First and foremost there was a cadre of highly talented cryptanalysts at Bletchley. These were the minds who came up with solutions to problems.

Those solutions were then taken away and industrialised – a process that required a whole separate pool of people. Not necessarily people who had Cambridge degrees. These were clever, able recruits who had a reasonable high school education.

They came in, in their thousands, and were often given very dull jobs to do. But they were part of a chain that allowed thousands of messages to be decrypted and understood every day.

A statue of Alan Turing, one of Bletchley Park’s leading mathematicians.

The officials behind Bletchley Park recognised that it’s not good enough just to have geniuses like Alan Turing, you also need people who can enable that cleverness. The combination of these two types of people is what really made Bletchley a success.

Not only were they responding to the different codes that Britain’s enemies were using, they were also devising ways to break those codes on an industrial scale. This was absolutely key – reading one enemy message doesn’t really help you but reading a thousand enemy messages gives you a massive advantage.

Such demands meant that Bletchley was in a constant race to build more facilities, to hire more staff, to train people and to generally expand the operation, all the time knowing that if the Germans made one slight change to what they were doing, the whole plan could collapse like a house of cards.

Not only were they responding to the different codes that Britain’s enemies were using, they were also devising ways to break those codes on an industrial scale.

Such crushing collapses certainly weren’t unheard of. One team spent most of the 1930s building the complete Italian naval codebook, only for it to be scrapped in 1940 when Italy joined the war. That team, some of whom had been at it for ten years, simply had to start again.

The stamina and the determination to take hits like that and just carry on was at the heart of Bletchley’s success.

Join Dan Snow on an exclusive tour of the house and grounds, as well as the little known but all-important cottages that surround Bletchley Park.Watch Now

What is the legacy of Bletchley Park?

A lot of people talk about the legacy of Bletchley Park in terms of electronic devices. They might look at the Bombe machine or at Colossus, which was an early form of electronic computer, and decide that Bletchley’s lasting impact was technological.

Such a conclusion misses the point though. Bletchley Park – all 10,000 people, from the boffins to the tea ladies – was essentially a big computer.

A reconstruction of one of the Bletchley Park Colossus Machines, the world’s first programmable, digital, electronic, computing devices.

Data, in terms of messages, was put in at one end and that information was processed in incredibly sophisticated ways, often by people sitting in a room and doing something very dull, sometimes by a machine, sometimes by being written on index cards. And out of the other end came intelligence and decrypted information.

Bletchley showed us how to organise people to get a job done and how to process data in large volumes.

It’s that organisation, not just of machines but also of people and of talent, that produced a result. This is why today’s big companies, not only IT companies but corporations of every variety, owe a debt to Bletchley Park.

Bletchley showed us how to organise people to get a job done and how to process data in large volumes. These lessons were much more to do with humans than machines.