In World War II, Germany used a mechanical encryption system called an Enigma machine. The Allies mounted a huge effort to figure out how to decrypt messages encoded by the Enigma, and one offshoot from that effort was, in part, electronic digital computers. As for the Enigma itself, the Allies may not have realized that they could have simply purchased one. Before the war began and the German Navy adopted it, the Enigma was a commercial product.
The Enigma was invented by Arthur Scherbius, who was born October 30, 1878, in Frankfurt, Germany. He became an electrical engineer and earned a doctorate in engineering in 1903. He worked for a number of electrical companies in Germany and Switzerland, and came up with inventions from new types of asynchronous electric motors to ceramic heating systems. He did research, too, and the Scherbius principle, which applies to asynchronous motors, is named after him.
He eventually founded his own company, Scherbius & Ritter, in 1918. He very likely founded the company because of his latest patentable idea: an encryption machine. It used rotating wheels with letters, and you would set them in a particular configuration, then type a message on the attached typewriter keyboard. The machine substituted new letters for the ones you chose, and produced a coded version of your message. Someone else with another machine could use the same configuration settings and enter your coded message to get the plain text version. It sounds simple, but because there were five wheels with 26 positions each, that yields 158,962,555,217,826,360,000 possible settings. The only flaw — and it was the flaw that Alan Turing used to help crack the code — was that no character was encrypted as itself.
Scherbius marketed his machine as the Enigma in the 1920s. The German Navy bought one in 1926, and the German Army adopted the system a few years later. But otherwise the machine was not very popular; in the 1920s there were very few companies or individuals who felt they needed to keep their messages secret. At least not that secret.
The machines didn’t become widely used until their military applications starting in the 1930s. But Scherbius didn’t live to see it; he died at age 50 in a horse-drawn carriage accident in 1929.
