Operation Fortitude South, the deception campaign that helped make D-Day a success.
During World War II the Allies were the unquestioned masters of deception and trickery. The spooks of Bletchley Park had decrypted Germany’s enigma code, and unbeknownst to them the Allies were listening in to every secret German message. The British had spies, secret agents, and double agents everywhere, and were masters of rooting out and eliminating enemy spies. OSS agents supported resistance groups all over the Third Reich, who harassed German troops and sabotaged enemy infrastructure. When the Allies invaded North Africa in 1942 they tricked the Germans into thinking they would invade Norway. When the Allies invaded Sicily in 1943 they tricked the Germans into thinking they would invade Greece. The Normandy Operation involved no less subterfuge, and in fact an entire disinformation campaign called Operation Quicksilver would help make the Normandy invasion a success.
Operation Fortitude was a campaign within a larger campaign to fool the German high command into believing that the great invasion would come at any place other than Normandy. The emphasis of Operation Fortitude South was to trick the Germans into believing that the invasion would occur at the Pas-de-Calais, located 200 miles up the coast from Normandy. Calais was a reasonable choice for an invasion, being the narrowest part of the English Channel and the port used the English to invade France during the Middle Ages. The deception was built of two parts; the ghost army and the misinformation campaign.
To make the invasion believable, an entire fake army was created called “The Ghost Army”. The hypothetical invasion of Calais involved a fictional 1st US Army Group to be commanded by Gen. George S. Patton. An entire fictitious army was created to fool the Germans, which included fake buildings made of plywood, tent encampments, inflatable dummy tanks, dummy trucks, fake landing craft, and fake aircraft. To make the army seem real, loudspeakers broadcasted engine noises, artillery sounds, and other camp noises to recreate the sound of a busy encampment. Such tactics were developed by a British stage magician named Jasper Maskelyne, who was notorious for using trickery and illusion to make whole armies appear and disappear during the North African campaign. To complete the deception Gen. George Patton himself inspected the camp, giving speeches and posing for photo’s with his fictitious men, photo’s which were conveniently “leaked” to German intelligence.
The second part of the deception was the misinformation campaign, which utilized more cloak and dagger than the Ghost Army. Allied communications broadcasted bogus messages which included fake orders and communications between Allied High Command and the Ghost Army. Finally the British Secret Service leaked false information to German Intelligence through the use of double agents, German spies who had been convinced to defect to the Allies.
The Germans took the deception hook, line, and sinker. As a result of Fortitude South the fortifications of the Atlantic Wall were strongest at Calais and the bulk of German forces were stationed at Calais as well. More importantly most of Germany’s Panzer (tank) forces were situated near Calais to repeal the fake Allied invasion. It is very fortunate the Allied forces did not have to face German Panzers during the opening days of the Normandy Invasion. In fact the deception worked so well that even as Allied forces were storming Normandy, Hitler ordered his troops to remain in Calais, believing the Normandy invasion to be an Allied trick. By the time it was realized that Normandy was the real invasion, it was too late.