Rare Alan Turing wartime papers saved for the nation after export bar

A collection of rare project writings by Second World War codebreaker Alan Turing has been saved for the nation after an export bar was placed on them to prevent them being taken abroad.

The wartime documents are valued at more than £397,000 and relate to the Delilah project, which developed a portable encryption system for use in military operations.

They were saved for the nation after an export bar was placed on them and then funds were raised to buy them – including £250,000 from algorithmic trading firm XTX Markets.

There was also a £20,000 grant from the charity Friends of the Nations’ Libraries, and more than £97,000 from the National Heritage Memorial Fund, private donations, and King’s College, Cambridge.

The documents will join the largest collection of Turing-related documents at King’s College, Cambridge and – once digitised – they will become part of the Turing Papers online archive, freely available to scholars.

Following Turing’s ground-breaking work on the Enigma machines at Bletchley Park, he began work on the Delilah project at Hanslope Park to develop a portable encryption system or voice scrambler to protect military secrets in the field.

Turing rarely kept notes and correspondence (King’s College Cambridge/ PA)

The papers consist of more than 40 pages of unpublished Delilah project notes written by Turing and colleague Donald Bayley.

Unpublished evidence of Turing’s work has rarely survived.

Turing himself did not usually keep research notes, working drafts or correspondence.

Secretary of State for Culture, Media and Sport Lisa Nandy said: “It’s brilliant news that the Friends of the Nations’ Libraries charity has successfully campaigned to save Alan Turing’s vital notebooks.

“Turing was not only a pioneering figure in science and mathematics, but also a national hero.

“This is a powerful example of what can be achieved when private and charitable sectors come together.

A collection of rare project writings by Second World War codebreaker Alan Turing, the Delilah papers, has been saved for the nation (King’s College Cambridge/ PA)

“After a Government export ban was placed on the notebooks, this collaboration has ensured that these treasures will be preserved for years to come.”

Turing arrived at King’s College as an undergraduate in 1931 and was made a Fellow in 1935.

The Turing Archive was founded in 1960 following a donation of his papers by his mother, Sara Turing.

King’s College Provost Gillian Tett said: “Alan Turing’s work laid the foundations of computer science, artificial intelligence and much of our modern world.

“We are honoured to house the ‘Delilah’ papers at King’s and are deeply grateful to our partners in this endeavour.”

Geordie Greig, Chair of Friends of the Nations’ Libraries, said: “This extraordinary private donation means that crucial papers written by one of Britain’s geniuses have been saved and can studied at Cambridge.”

Alex Gerko, Founder and co-chief executive at XTX Markets, said: “The ‘Delilah’ papers are a unique collection of notes from one of the nation’s greatest mathematicians.

“It’s important that this archive remains in the UK and is made publicly accessible, so we are thrilled to be part of that effort.”