Turing was an English boy who, by good luck, happened into the right people at the right time. His genius for mathematics was discovered by the British military as World War Two was in progress. At that time, the Germans were using an extraordinarily complex communications code which the best Allied minds couldn't break. The British created a project at Bletchley Park (about an hour from London) which was totally dedicated to the work of breaking and deciphering the German Code. Called the Enigma Project, it was critical to the war effort.
Turing, considered by his peers to be an "eccentric," had an extradordinary gift for ciphers. At Bletchley, he was allowed the personal and intellectual freedom to work in his own way, and as a result he became the one man who could break the German Enigma code. In essence, he "reverse engineered" the GermanEnigma Machine and broke the enemy code. To work out the details of his decoder, he shut himself into his room for days -- lowering a pail out the window for meals. On his own, during a two-week period, he literally invented the basic design of the electronic computer (Colossus). Once Colossus was actually built from Turing's plans, intercepted German messages could be read and understood -- and counterplans could be made to win the war.
One story is told of Turing, who had a bad case of hay fever, cycling into the next town to buy a few necessaries -- wearing a gas mask. To Turing, who was almost certainly autistic, the gas mask was a logical preventive measure to keep away the pollen. To the people of Bletchley, of course, a military scientist in a gas mask was a terrifying sight!
Sadly for Turing, the combination of his autism and his homosexuality was his undoing. Though his world could comprehend an "eccentric genius," it could not handle an openly gay man. Although he was honored for his achievements, he was finally dishonored for his sexuality. After WWII ended the Colossus computers (many were built) were destroyed under orders that everything done at Bletchley Park was to be kept secret for thirty-five years. In 1996, however, the Colossus computer was rebuilt at the Bletchley Park museum.
Anyone interested in learning more about Alan Turing may want to read his biography, or perhaps view the BBC videos made a few years ago. Derek Jacobi starred as Turing, and did a wonderful job recreating the autistic savant who, very possibly, was instrumental in winning the second world war.