Fortitude

The goal was to convince the Germans that the Allied invasion would strike at the Pas-de-Calais, across the narrowest part of the Channel from Dover, and that the landings in Normandy were only a distraction not worth defending. To sell this picture, planners fabricated hundreds of false agent reports and invented an American army group that did not exist. Phantom radio traffic was broadcast, and inflatable tanks, balsa and canvas bombers, and dummy landing craft were arranged where Luftwaffe reconnaissance could photograph them.

This deception operation, known as Fortitude and part of the wider Operation Bodyguard, is documented here in the official history of the whole effort. Roger Hesketh wrote it as the head of the team of specialists responsible for the D-Day deception, and it has now been declassified and published.