Operation Fortitude proved key to diverting German forces away from the Normandy landings (Operation Overlord). It aimed to create the illusion of two alternative invasion forces, one targeting Norway (Fortitude North) and one targeting Pas de Calais (Fortitude South). It was a joint venture between numerous Allied military deception agencies, which often proved problematic due to distrust and rivalry. Both operations employed so called ‘special means’, such as the placement of phantom armies and planes, to trick German surveillance into thinking that troops were amassing in different areas. Dummy radio communications were broadcast concerning both sites, although these are now thought to have been ineffective in the case of Fortitude North. The most important aspect of both operations was the use of double agents to supply false information to German intelligence, whilst similar operations such as Graffam and Royal Flush aimed to leverage diplomatic contacts in neutral countries to leak false information.
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