The overwhelming impression of D-Day in this country is that once the Allies were established ashore on the first day, victory was simply a matter of time. But those who assume that the success of Operation Overlord was inevitable should think again. That at least is the opinion of old Nazis, extreme nationalists and neo-Nazis, as websites and books in Germany today still emphasise. In their view, the Wehrmacht's defeat in Normandy was entirely due to treason.

This belief was openly encouraged by the Nazi regime in the wake of the 20 July plot against Hitler. The attitude was that we have at last dealt with the traitors in our midst, and now we can get on with winning the war. That such a distorted view of history can still persist 65 years later shows that the Nazi mindset has forgotten nothing and learnt nothing.

They cite that although the German 15th Army in the Pas de Calais had been put on full alert during the night of June 5, after the interception of a BBC message to the French Resistance, the 7th Army in Normandy did nothing. The commander-in-chief of the 7th Army, because of the forecasts of bad weather, had organised a command exercise in Rennes, far from the invasion front, which meant that almost all divisional commanders were away from their formations. All this, in their view, points to a sabotage campaign by Generalleutnant Hans Speidel, Rommel's chief of staff. Speidel is described as the centre of “the cancer of treason in the German armed forces in the West”. One book is even entitled Treason in Normandy: Eisenhower's German Helper.

Speidel was in charge at Army Group B headquarters because Rommel, in the belief that the stormy weather made an invasion unlikely, had returned to Germany. It was his wife's 50th birthday and he intended to see Hitler to persuade him to deploy more panzer divisions in Normandy.

Everything that went wrong on the German side is thus attributed to a conspiracy, mainly organised by Speidel. “Speidel is . . . demonstrably the great traitor of the German defence against invasion,” one site declares. There are even claims that orders had been issued to flak batteries not to open fire, a preposterous assertion as both the British and American airborne forces found to their cost.

Speidel is accused of sending the 21st Panzer Division on a wild-goose chase down the west side of the River Orne early on June 6; in fact it was the local commander who ordered it to attack the British airborne landings on that flank. He is also accused of thwarting the movement of three Panzer divisions towards the invasion area. This is said to have been part of his plot to hold back two other Panzer divisions in order to help the July plotters to seize Paris a month and a half later. Thus the conspiracy theorists seek to transfer the blame away from Hitler, who would not allow panzer divisions to be released without his command.

Speidel, who ironically had been Hitler's guide on his only visit to Paris, was a key member of the 20 July conspiracy. But to pretend that he had sabotaged the defence of Normandy on June 6 is ridiculous. After the July plot, he escaped the Gestapo by a miracle, which perhaps explains the Nazi vituperation against him. In the 1950s he became a senior officer of the West German Bundeswehr and later a Nato commander. The Nazis and neo-Nazis see this as his payoff for having helped the Allies. In their paranoid vision, they claim that he “had always been an American”.

Even the Luftwaffe, the most loyal of all the services to Hitler, is accused of treachery. The blame here is laid at the door of General Adolf Galland, the Luftwaffe's fighter chief. It is implied that he deliberately prevented the reinforcement of the squadrons in France. The Leonidas Staffel, a kamikaze squadron, is said to have been prevented from attacking the Allied battleships. And so it goes on.

The SS also suspected treason within German military intelligence, because it swallowed Fortitude, the Allied deception plan. Fortitude convinced the Germans that a fictional 1st Army Group was to invade the Pas de Calais after the Normandy landings. It worked for far longer than the Allies had ever dared to believe, right up into August, and forced the Germans to keep the bulk of the 15th Army in the Pas de Calais.

But because some senior officers of the Abwehr had been involved in the resistance against Hitler, the SS became convinced that their gullibility was part of a wide ranging conspiracy to destroy the Nazi regime. Thus Normandy formed the great stab-in-the-back legend of the Second World War. Yet unlike 1918, the traitors this time were not Jews and communists. They were aristocrats and officers of the general staff.

Antony Beevor is author of D-Day: The Battle for Normandy

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