To disrupt German morale during World War II, the Allies hatched a plan to send anti-Nazi propaganda to German citizens through the mail. They quizzed prisoners of war about the German postal service and drew on local telephone directories to identify 2 million addressees who might receive forged letters and subversive material. Then the letters were loaded into counterfeit mailbags and dropped near destroyed trains in the hope that they’d be collected and delivered.

By 1945 twenty missions had been completed, but by then many German homes had been destroyed and their inhabitants killed or displaced, so the operation had limited effect. Above is a striking stamp prepared for the effort — the subscript on the “death head” stamp reads “Futsches Reich” (ruined empire) rather than “Deutsches Reich” (German Empire). Altogether 96,000 stamps were prepared for the effort, but the “death head” stamp may never have been used.