“Bermuda proved a geographically convenient location for the scrutiny of mail exchanged between North America and Europe. All correspondence sent to or from Europe was examined by Imperial Censorship staff based at the Hamilton Princess Hotel, and suspect items were intercepted and photographed.
“This led to the identification of several German spies, among them George Nicolaus and Joachim Ruge.”
But its most celebrated case involved the Bermuda censorship operations playing a key role in the uncovering of the largest Nazi espionage operation in America.
It was operated by Kurt Frederick Ludwig in 1940-41 and the network became known as the “Joe K” spy ring because it was the code name used in letters sent to Berlin addresses giving information on Allied shipping in New York Harbour and other sensitive military information. Details of the ship movements the ring provided were passed on to Nazi submarines operating in the Atlantic and a number of UK-bound vessels were torpedoed as a result."