Hitler and his military advisers were expecting an Allied offensive in Europe in 1944. Directive No. 51 of 3 November 1943 stated that ‘Everything indicates that the enemy will launch an offensive against the Western Front of Europe, at the latest in the spring, perhaps even earlier’, and that Hitler had decided to reinforce Western defences, ‘particularly those places from which the long-range bombardment of England will begin’.
Once the Allied decision to launch OVERLORD had been taken at Teheran, instructions were given for a major deception exercise, Operation BODYGUARD, to persuade the enemy to dispose his forces in areas that would least interfere with OVERLORD and ANVIL, and to deceive him as to the strength, timing and objectives of those operations.
An elaborate set of deception plans was implemented, including those designed to indicate a possible Allied attack on Norway (FORTITUDE North) and in the Pas de Calais region (FORTITUDE South), to inflate in the enemy’s mind the strength of Allied forces available for the invasion.
The credibility of these plans was enhanced for the German High Command by intelligence received from double agents like Juan Pujol (GARBO) and Roman Czerniawksi (BRUTUS), who supplied, on MI5’s instructions, reports from imaginary networks of agents.
As D-Day approached, elaborate physical deception plans were set in place, involving dummy aircraft and landing craft, simulated wireless traffic and an entire bogus US Army Group. The cumulative effect was of misdirection and confusion, as intended.
Also crucial to Allied success was the parallel deception plan mounted by the Soviet High Command: Operation BAGRATION, named after a Georgian general in the Napoleonic Wars.
By the spring of 1944 most of the Ukraine and Crimea had been liberated from Axis control, and the Soviet High Command were planning a major attack against the German Army Group Centre, the only significant German force still on Soviet territory, stationed at Minsk in Belorussia.
The Germans expected an attack from the south. BAGRATION, which involved the creation of two entire dummy armies, diversionary earthworks and the stationing of anti-aircraft artillery in the area where the Germans expected to find it, persuaded them that attack would come from the south, and not until the end of the summer.
Nor were they aware that Stalin, who had his eye on a conclusive victory and a swift advance across Eastern Europe, had massively increased the Soviet forces available for the real attack, which began in the north shortly after D-Day.
BAGRATION, together with BODYGUARD and other deception plans, ensured that in May 1944, just before the Allied invasion, the Germans had no idea how many forces they would be facing on either the eastern or western front, where they would attack, or when.