Local 100-year-old’s secret past as Bletchley Park codebreaker

Not many people can look back on their lives knowing they helped change the course of history.

But Newton Abbot resident Jo Birch, who celebrated her 100th birthday earlier this month, is one of those who can do just that.

She was among the women who worked behind the scenes at Bletchley Park, - the top secret, Buckinghamshire-based centre of codebreaking during the Second World War. Their job involved intercepting and deciphering the encoded messages exchanged by the German military, including tactical operational orders and troop movements.

The information they were able to pass on was key to the Allied forces’ victory over the Nazi regime. It’s thought to have shortened the war by two to four years, saving thousands of lives..

But this ground-breaking and operationally crucial work was kept strictly under wraps at the time and for decades afterwards.

Everyone who worked at Bletchley Park had to sign the Official Secrets Act, so their role in changing the course of history didn’t come to light until the information was declassified in the 1970s.

Jo Birch was one of the operators of the Bombe electro-mechanical machines invented by Alan Turing and used in decryption of Enigma signals – the coding system which the Germans believed to be unbreakable.

She was recruited from the WRNS and based at one of Bletchley Park’s outstations, Gayhurst Manor in Newport Pagnell, between 1941 and 1943. These Wrens were called the Gayhurst Girls. She later moved to another outstation, Stanmore in north-west London.

Speaking on her 100th birthday, Jo said she could remember her days as a wartime codebreaker at Gayhurst Manor:

“It was home - we had to live there.

“It was a frightening time, but it was very interesting - very exciting.”

She said the work was sometimes difficult when the machine broke down and no decoding could be done - but she clearly remembered “some Americans” coming to fix it, and then announcing, “We’re back in business, boys!”

Jo is listed on the Bletchley Park Roll of Honour under her maiden name, Ellen Joanna Blake - the Roll notes that her colleagues called her ‘Blakie’.

She has also received her Bletchley Park commemorative badge - these were issued from 2009 onwards, after the Government and GCHQ officially recognised the service of the thousands of codebreakers.

She has attended reunions of surviving Bletchley Park workers, and was presented with a certificate granting her ‘Freedom of Bletchley Park’ for her ‘contribution to the work undertaken at Bletchley Park during World War II’.