A woman who helped crack Nazi coded messages during World War Two has died.

Dorothy Du Boisson, MBE, who worked for the Ministry of Defence (MoD), operated a code-cracking machine – the Colossus – at Bletchley Park.

Messages gleaned from the equipment had a huge impact and “rewrote the course of World War Two”.

In June 1944, the Allies were debating when to go ahead with the invasion of Europe – D Day.

Eisenhower’s decision was directly influenced by information revealed by Colossus, which was operated by the Ministry of Defence but subject to strict secrecy laws.

Miss Du Boisson, who lived off London Road, Brighton, suffered an infection and died in hospital on February 1, aged 93.

Her family said she was active to the last, travelling abroad in January.

Her nephew Richard Du Boisson, 62, who now lives in the South of France, said: “She was so modest about her achievements and none of us knew much about what she had achieved.

“Earlier this week we were clearing her home when we came across her signature on documents about the Official Secrets Act – that was what she was like.

Changed history

“She always played down her past.

“In her job the codes would come in and she would enter them all.

“It was a huge team effort and the team rewrote the course of World War Two and changed history.

“She never let on she had an MBE and would just say, ‘oh everyone was talented’.”

He said his aunt was a keen traveller, an avid birdwatcher and loved family history.

Pictures online show Ms Du Boisson, who moved to Brighton in 1970, operating the computer which was developed at Bletchley Park, the site of the Government Codes and Cipher School.

Miss Du Boisson’s funeral will be held at 4.30pm today (Wednesday, February 13) at the Woodvale Crematorium and later at the Old Ship Hotel, Brighton.

See the latest news headlines from The Argus:

More news from The Argus

Follow @brightonargus

The Argus: Daily Echo on Facebook - facebook.com/southerndailyecho Like us on Facebook

The Argus: Google+ Add us to your circles on Google+