Much of Turing's work was classified as Official Secret until the mid 70s. Declassification allowed the the publication of The Ultra Secret that first revealed

Much of Turing's work was classified as Official Secret until the mid 70s. Declassification allowed the the publication of The Ultra Secret that first revealed what went on at Bletchley. Two of Turing's papers on cryptanalysis were thought significant enough to remain classified by GCHQ for 70 years. Yet he was still fairly well known. Obviously after the release of the wartime work his place in history grew. It was only after that declassification of Bletchley that anyone heard of Tommy Flowers and his work at GPO research. Up til that point even his family didn't know his contribution. Flowers should be far better known than he is, but anyone encountering the Enigma codebreaking story in the last 40+ years should come across his story. I do think it criminal they got so little official recognition.