During World War II, Allied invasion plans for Sicily were an open secret to Axis commanders due to the island's obvious strategic importance. To trick Nazi Germany into believing the Allies intended to invade Greece and Sardinia instead, British Naval Intelligence officers Ewen Montagu and Charles Cholmondeley conceived Operation Mincemeat. They obtained the corpse of Glyndwr Michael, a deceased homeless Welshman who had died from ingesting rat poison, and created a meticulously detailed fake identity for him: Major William Martin of the Royal Marines.
The officers filled Major Martin's pockets with personal items, including love letters from a fictional fiancée named Pam, a receipt for an engagement ring, theater ticket stubs, and an overdue overdraft notice from his bank. Crucially, they attached a briefcase to his wrist containing fabricated personal letters between high-ranking British generals indicating that the Allied targets were Greece and Sardinia, with Sicily merely serving as a feint. In April 1943, the submarine HMS Seraph released the corpse off the coast of Huelva, Spain.
Local fishermen retrieved the body, and Spanish authorities handed the sensitive military documents over to German intelligence agents operating in Spain. The Axis High Command took the bait completely. Adolf Hitler reordered divisions to Greece and the Balkans, while General Erwin Rommel was dispatched to Greece to oversee defenses.
When the Allies invaded Sicily on July 10, 1943, Axis forces were caught unprepared, vastly reducing Allied casualties and shortening the Mediterranean campaign.