British mathematician and computer scientist Alan Turing was convicted of "gross indecency" in 1952, before being sentenced to chemical castration. Now, 59 years after his death from cyanide poisoning in an apparent suicide, he has been issued a posthumous pardon by Queen Elizabeth. Turing — who was instrumental in cracking the Nazi Enigma code during World War II and designed ACE, one of the world's first stored-program computers — received the conviction for his homosexuality, and underwent a series of injections that left him impotent and growing breasts.

The pardon was granted under the Royal Prerogative of Mercy after a request from Chris Grayling, the British government's Justice Minister, and comes after a lengthy campaign to secure an apology for Turing's treatment. In 2009, a petition requesting a pardon prompted then-Prime Minister Gordon Brown to issue an apology for Turing's "appalling" persecution. Another petition created in 2011 was denied by Lord McNally after he said Turing was "properly convicted." In 2012, Liberal Democrat member of parliament Lord Sharkey introduced a bill calling for a royal pardon that made it to a second reading in the House of Lords earlier this year.

Turing was convicted of indecency for his homosexuality

The pardon is an apology to one of the 20th century's most influential scientists. Turing's work laid the foundations for modern computing, and his codebreaking efforts at the British Bletchley Park campus during World War II were so advanced that some details of his research were only released in 2012. Although Turing died in 1954, many of his creations and concepts — such as the Turing test used to judge artificial intelligence through conversation — live on in our modern technology and media.