LONDON.- On 14 July 2015, Sotheby’s London will offer a rare and exceptionally well-preserved example of the World War II cipher machine, The Enigma. This small machine had a huge impact on the course of 20th-century history, playing a critical role in the extraordinary code-breaking story that unfolded at Bletchley Park (recently celebrated in the award winning film ‘The Imitation Game’) and the birth of the computer age.

The Imitation Game
Used by Nazi forces during World War II to transmit coded messages - and with around 159 million million million possible settings - the German command was convinced that the Enigma machine produced an unbreakable code. The Enigma set a challenge that was famously answered by Alan Turing and the team at Bletchley Park, whose ground-breaking work is said to have shortened the war by two years and saved up to 22 million lives. Furthermore, by coming to the understanding that to defeat Enigma it was necessary to mechanise much of the work of decryption, they helped pioneer ground-breaking developments at the dawn of the computer age.

Breaking Enigma was the work of many, including Polish cryptographers who had already begun to decrypt Enigma traffic before the war; naval forces who risked their lives capturing Enigma machines and code books; Alan Turing and other mathematicians with their revolutionary models for deciphering; Tommy Flowers and other mechanical geniuses who designed 'Colossus', the world's first programmable computer and the hundreds of Wrens who operated the machines that made the daily decrypts possible.

The heroic and tragic story of Alan Turing in particular, whose work provided the key to breaking the wartime Enigma codes, has captured the public imagination in recent years. Following the war, his vital role at the heart of Bletchley Park remained classified by the British government. In 1952 Turing was prosecuted for homosexual acts and he accepted chemical castration as an alternative to a prison sentence. He died in 1954 from cyanide poisoning having never received public recognition for his remarkable work. In 2009 the British Prime Minister Gordon Brown issued a public apology for "the appalling way he was treated" and Queen Elizabeth II granted Turing a posthumous pardon in 2013. He is now regarded as one of the heroic figures of World War Two and one of the fathers of computer science.

Exceptionally Rare
Few Enigma machines survived the War intact: the Germans destroyed them as they retreated, and for decades after the war governments around the world kept close control over Enigma technology (indeed, two of Turing's wartime papers on cryptography remained classified until 2012). So secure was the system believed to be that some governments, unaware of the work of Bletchley Park, continued to use Enigmas after 1945.

The Service Enigma Machine (Enigma I), estimated £50,000-70,000, will be offered as part of Sotheby’s English Literature, History, Children’s Books and Illustrations Sale on 14 July 2015.