Before Enigma: The Room 40 Codebreakers of the First World War

How did the British codebreakers succeed in cracking the apparently unbreakable Enigma code during the Second World War? Was it their gifted amateurism? The brilliance of Alan Turing? The invention of the very first computers? Or the pioneering work of Polish cryptographers? It was all of the above. But there is one other crucial factor, which is much less well known. The same team had done it before. The truth is that many of those most closely involved in cracking the Enigma code - Alista...