Abstract :
Many academic and almost all popular accounts present World War II cryptographic and cryptoanalytic activities as an interplay between Nazi Enigma cipher devices and Allied code breakers at Bletchley Park. To a lesser extent, academics have also documented the cryptoanalytic activities at the US Naval Communications Annex. However, a third center of Allied code breakers was located at the US Army´s Arlington Hall Station, and its existence and activities are largely missing from the public record. Allied cryptanalysts began their attack on the Axis cipher systems, first mathematically and then later with machines. The code breakers used specialized machines such as the Bombe and Colossus, as well as modified and unmodified office equipment.