Bletchley Park main building exterior

Bletchley Park: What was its role in WW2?

Bletchley Park main building exterior

In the Second World War, Bletchley Park in Buckinghamshire was the site where British codebreakers worked to thwart Nazi Germany through breaking coded messages.

To those who worked there, it was known by several different cover names, including 'Station X', and 'B.P.'

Established in 1938, the intelligence generated from the site's huts had an impact on all services involved in the war effort.

The Enigma machine used by the German military had the potential for nearly 159,000,000,000,000,000,000 combinations when creating ciphered messages.

In response, the UK created its own team in order to break the complex system.

Dilly Knox, a codebreaker from the First World War, recruited a crack group, including Alan Turing, to begin working out of Bletchley Park's collection of small buildings.

Using an Enigma machine, encrypted messages were sent from Berlin using the Lorenz rotor stream cipher machines, to German troops in the battlefield.

The Germans' system of ciphering was changed every day from the start of the war, in order to make messages more difficult to understand.

German Enigma machine
An Enigma machine on display at Bletchley Park (Picture: PA).

The efforts of Mr Turing and his team are credited with shortening the war in Europe.

The team in Buckinghamshire were able to counter the techniques and technology being used by Germany with their own creations.

The giant Colossus machine reduced the time it took the team to decrypt messages from weeks to hours, while Turing's Bombe, originally designed by its namesake, was an essential tool in unlocking parts of the Enigma code.

Once the first German coded messages were deciphered in early 1940, the team at Bletchley Park was on its way to victory and by 1944, more than 3,000 German messages were being decrypted every single day.

Significant results were seen in the skies above Europe, as messages to the German Luftwaffe were cracked, allowing Britain to anticipate the aircraft's whereabouts.

This meant the RAF was often one step ahead, providing opportunities to surprise German pilots in the air, while bombing could be better defended from the ground.

This breakthrough proved crucial for the Allies' success in Normandy during D-Day.

Turing Bombe machine
One of the UK's big hitters in their decoding arsenal – the Turing Bombe machine (Image: PA).

The work done at Bletchley Park also impacted the war being fought at sea.

Cracking the 'Dolphin Enigma' was critical as this was the coding system used by Germany's U-boats at sea.

Figuring this out and cracking the Italian ciphers lead to key victories, including in the Battle of Matapan which saw a Royal Navy victory in the Mediterranean.

General Dwight D. Eisenhower, then the Supreme Allied Commander, Allied Forces, expressed his gratitude to the Bletchley Park team in a letter.

"The intelligence... has been of priceless value to me," he said.

"It has saved thousands of British and American lives."

The future US president ended his letter by expressing his "sincere thanks" to the codebreaking team "for their very decisive contribution to the Allied war effort".

The British public did not find out about the work of the codebreakers or their role in the war effort until the mid-1970s, due to the Official Secrets Act.

Watch: A rare glimpse of MI6 communication staff at Bletchley Park during the war.

Last April, unique footage surfaced of MI6 communication staff at Bletchley Park during the Second World War.

It is the only known footage of Whaddon Hall, a secret site connected to Bletchley Park, from World War Two.

Whaddon Hall was sent Ultra intelligence, a classification given to intelligence produced by the Government Code and Cypher School (CG&CS) at Bletchley Park before it was passed on to Allied Commanders in the field.

In January 2020, the Buckinghamshire country home celebrated 80 years since it cracked the Enigma code, sharing stories of the crucial codebreaking work on Twitter.

In August, Bletchley Park announced it could lose more than a third of its staff after the Bletchley Park Trust proposed a restructuring due to the COVID-19 pandemic.

The closure of its museum and park from March until early June last year meant a loss of more than 95% of its income, and the trust anticipated a loss of about £2m last year.

However in October 2020, Facebook made a £1m donation to Bletchley Park to support its work for the next two years.

The social network firm said the donation was to recognise Bletchley Park's legacy as the birthplace of modern computing.