The story of codebreaking at Bletchley Park during the Second World War and its massive contribution to the British war effort is probably one of the most important stories of the 20th century.
Mathematicians and analysts broke encrypted codes sent by the German Luftwaffe, army and navy and in doing so, both directed our war strategy and saved lives.
The Enigma code machine had been adopted by the whole German military machine as their method for encoding signals. They [the Germans] believed their code was completely unbreakable and that therefore their radio traffic was absolutely secure.
But at Bletchley, they worked it out, and cracked the codes on a daily basis.
Read more about what happened at Bletchley Park
Many people worked on the machines that did this. The settings on the Enigma machine were changed everyday so the new settings had to be found and they had to be found quickly, if you wanted to have any chance of using the information.
Each person was an important cog in the wheel, but none of them knew what the other cogs in other huts were doing, until the mid 1970s when the secret began to emerge. Now, the important role it played during the war has gained Bletchley Park worldwide fame.
You can visit Bletchley Park daily (except Christmas Eve, Christmas Day, Boxing Day and New Year’s Day) to find out more, and they also hold regular events for all the family.
On May Bank Holiday Monday they held a Forties Family Festival with World War II re-enactors, a 1940s Lindyhopper dance troupe, and other 1940’s attractions, including a flypast by a Lancaster and the Red Arrows.
There was also a range of talks about codebreaking, including one from a former Bletchley Park Wren.
Jean Valentine worked on the Bombe codebreaking machine during the Second World War and now works as a guide at the centre. Her fascinating stories about life at Bletchley make the era come alive, and she told me more about exactly what went on.
How did you get to work at Bletchley Park?
Jean: People ask me this all the time and I don’t really know the answer. They ask did you volunteer, but how can you volunteer for something that nobody has ever heard of?! I think probably I was selected because you fill in forms when you plan to join anything, and I think the form that I filled in said something about hobbies, and I think that I said cryptic crossword puzzles. And that was enough, because they were looking for linguists and mathematicians and people who could think laterally.
What was your actual job at Bletchley Park during the war?
Jean: I looked after a machine called the Bombe, which was absolutely essential. It was needed to find the settings on the rotors of the German encryption machine Enigma and without the settings on the rotors, you would never break into it because the Enigma was so complicated, it could encrypt up to 158 million, million, million possibilities.
Jean Valentine with the Bombe in more recent times
What we did is put a menu into it, which was a crib, and the [Bombe] machine looked for the settings. When it had found them, we wrote down the answers that were on the indicator drums and we rang them through to an extension number which I now know was Hut 6. They used these letters to see if they would manage to break into the German encryptions – but I didn’t know that then! I knew somebody did it somewhere but I didn’t know where!
These machines did the equivalent work of 36 Enigmas and 200 of them were working 24 hours a day, both here and at our various outstations. Bletchley Park wasn’t a place on its own, you can’t have a place like this without back up, so we had two [outstations] in Middlesex, at Stanmore and Eastcote, and three in Buckinghamshire, at Adstock, Gayhurst and Wavendon.
Did you know exactly what you were doing and what it was for?
Jean: Well, I knew what I was doing but I didn’t know what anybody else was doing. I worked in Hut 11 here and I now know that we were working in close conjunction with a hut across the pathway from us called Hut 3 and another called Hut 6. We were all working hand in hand but we didn’t know that.
How many people were you working with in your hut?
Jean: We worked in watches and in this particular hut there were approximately 11 people working at any one time. That was 33 throughout the day because one watch was always on duty or asleep or something like that.
We were ferried back and forth from where we lived. I lived in Steeple Claydon, a little village in Buckinghamshire. It was very strange because we lived in this requisitioned house, and people must have wondered where we were going and, when we came back, where we had been, but the secret never got out.
Did nobody ask? Did you not talk or was it that kind of culture where you just thought I know there’s something going on but we’re at war so we’re not talking about it?
Jean: We were told that if anybody said what are YOU doing, we had to say we were confidential writers. Now, a writer in the navy was a clerk, so we were confidential clerks if you like. And anybody who probed further having been told that was extremely bad mannered, people didn’t do it. So that’s what we said, but amongst ourselves, the minute we left the hut we were working in, we did not talk about what we had been doing at all. We were being driven by an MT driver and you don’t talk in front of people when you sign the Official Secrets Act. You’re told not to talk, you don’t do it.
Did you know what would happen if you did?
Jean: No, there was no threat made, we were put on our honour not to speak so we didn’t. And I never did, and none of my friends did, until it all started to come out of the woodwork in the mid 1970s. Then we were free to talk a little bit about it and of course now it’s just an open secret.
So these letters that you phoned through – probably changed the course of the war in some way?
Jean: Well it would certainly give people interesting information. They had a machine, that was actually our encrypting machine modified to mimic a German Enigma, and they’d set these letters up on the machine, type in the encrypted message and if it made sense when it came out, then we got the right answer. They then sent that into the red hut which was just over the pathway. They had translators there turning the German into English and also analysts who decided who should have this information and when they should have it.
When did you first know about the part you played, and how important it was?
Jean: Well, I always knew how important it was! But when I came to work here to train as a guide, I discovered that the telephone extension number that we had was actually for Hut 6 across the pathway. But it could have been anywhere. But it was across the path and we walked past it four times a day.
So you knew what your job was, but you didn’t know how what you were doing was affecting everybody else?
Jean: No not really, no. You just assumed that you were doing some good or you wouldn’t be there. We were paid this fantastic amount of money to do it you know! When we started we got 75p a week (15 shillings) and when we were good at the job we got a pound a week and then when I got promotion I got 25 shillings a week, it was riches beyond the dreams of avarice!
And over the years you’ve pieced it all together?
Jean: Only since it became public. For years, since the end of the war until the mid 1970s, I don’t suppose I even thought about it very much. I met up with one or two companions from those days but gradually people moved away or something and I lived abroad for years so I wasn’t coming in contact with the people I had worked with. But then when I started coming to the reunions, they said ,why don’t you come and train to be a guide?’ I said ‘no, I can’t drive nearly 40 miles, do a day’s work and drive 40 miles home’. Well, that was ten years ago and I’m still doing it!
So you got hooked?!
Jean: I suppose so, I mean, you meet a lot of interesting people doing this job. There’s sort of a club like atmosphere I suppose and I enjoy what I’m doing – but I don’t enjoy the drive!
How did you feel when you found out exactly what you’d been doing?
Jean: Well, nothing really. So many years had gone by and I’d done so many other things, it was just part of my life, nice to look back on, and nice to be able to come here and see people who had a similar experience to me. I was just one of a gang doing their best. When you think I could have been in a munitions factory or in a field digging up potatoes – no thank you! I was better off here!
It must be important to you now, to work as a guide here?
Jean: I want Bletchley Park to survive and looking out here today [on the Forties Family Fun Day] we are having an absolute bonanza. We’re absolutely swamped with people, there are thousands of them here today and that’s money in the bank and that is all important. We have been helped with the repair costs but it’s the actual running of the place [that we need money for]. The stewards and the guides that you see are all volunteers but the people who do things like the catering, the gardening and the maintenance have to be paid. And we need money to do that.
Did you ever think when you were working here, how it would affect the rest of your life?
Jean: No – not at all! And I wasn’t actually here very long. I had been here a short time when a notice went up saying that the following were required to go overseas [me included]. This was to Ceylon which is now Sri Lanka and I really didn’t want to do that very much because there were U-Boats and things out there. But it did say at the bottom that those who were underage had to get their father’s permission and I knew that my father wouldn’t let me go because I was precious – I was an only child and a teenager! So I went home and told him and he said, ‘you joined up to do your bit, so wherever they need you to go, you go – permission granted!’. And he didn’t even know where it was because I couldn’t tell him. I was gobsmacked. I didn’t know the word then but it’s a useful word now!
I suppose that’s the effect that being at war had on people?
Jean: Look, at that time we were fighting for our lives. My father had been a soldier in the First World War and he was used to discipline and his theory was that if command told you to do something then you did it, you didn’t argue, and you didn’t get out of it, you did it – so I did it.
I spent 15 months in Ceylon breaking Japanese cypher. I didn’t have a machine to do that, we were breaking the Japanese meteorological code which was all in figures, and it was really a case of getting down and working it out.
So did your hobby of doing cryptic crosswords help you in anyway with your work?!
Jean: I think it trains your mind in certain directions but I don’t know if it helped me or not. It’s just a different way of looking at things really.