The Duquesne Spy Ring was the largest spy ring in U.S. history. William Sebold was instrumental in rolling up the entire ring, and in doing so helped prevent the Nazi’s from conducting sabotage in the U.S. during World War II and also prevented the Nazi’s from having key sources of intelligence. The Nazi’s misjudged Sebold. It is true he had been a shiftless troublemaker, but he took his oath of U.S. Citizenship very seriously. Sebold deserves our collective thanks for the risks he took in this critical counterintelligence operation.
Sebold was a U.S. citizen who was pressured into becoming a spy when traveling to Germany (the Nazi’s wanted him to spy so ordered him to under penalty of death). Soon thereafter he became a double agent working for the FBI. He returned to the U.S. and was directed by his Nazi handlers to work with another of their agents, Fritz Duquesne. Fritz ran a ring of 33 agents which the Nazi’s had been building for years. They had built sabotage plans and stolen information and even some key hardware for the Nazis. They stole the plans for a key piece of equipment for enabling more accurate bombing, the Norden Bombsight.
Thanks to Sebold all were arrested in June 1941. The spies of the ring were convicted and sentenced, putting an end to the largest Nazi effort in the U.S.
Watch some of the surveillance video here:
For more on William Sebold see: Double Agent: The First Hero of World War II and How the FBI Outwitted and Destroyed a Nazi Spy Ring