Today is the 70th anniversary of D-Day, one of the greatest military victories ever won, when Allied forces invaded France on the beaches of Normandy, thereby beginning the liberation of Europe from Nazi control.

My mother, then a child living in Derbyshire, England, remembers hearing British planes passing overhead all night long on the evening of 5-6 June 1944, and the next day seeing the headmaster of her school run into her classroom, his gown flying, telling them that the long-anticipated invasion had finally begun.

Operation Overlord, as it was called, was a joint effort by the British and Americans, and was two years in the making.  It was devised by an Englishman, General Bernard Montgomery, the land force commander.  The supreme Allied commander, Dwight D. Eisenhower, was American, and his deputy, Air Chief Marshal Sir Arthur Tedder, and all three service chiefs were British, as was Air Marshal Sir Arthur Coningham, commander of the tactical air forces.

The Royal Navy had overall responsibility for Operation Neptune, the naval plan, which involved 1,213 warships, 200 of them American, and 892 British; and 4,126 landing craft, 805 of them American, and 3,261 British.

The US forces invaded two Normandy beaches, code-named Utah and Omaha, the British forces invaded the two beaches code-named Gold and Sword, and the Canadian forces invaded the beach code-named Juno, for a total of 156,000 soldiers and sailors of the Allied Forces.

Here is a 4-minute video of D-Day from the History Channel

The success of Operation Overlord lay in the great deception perpetrated upon the Nazis by the British. To vanquish the Nazis, the Allies needed to convince the Germans that they were about to invade elsewhere than where they actually did:  the beaches of Normandy.

They created a “fabric of lies,” as related by Ben MacIntyre, the author of Double Cross: The True Story of the D-Day Spies.  

“There was the real army which was assembling in Southern England, around Southampton, to invade Normandy. And then they created a completely fake army via the use of inflatable tanks and dummy airfields and dummy landing crafts to look like a real army.

“The essence of it was this fabric of lies put together by five spies, who just sent volumes of information apparently indicating the buildup of this enormous army that never existed. The idea being very simply that, if Hitler could be convinced that the attack on Normandy was simply a feint, a diversionary attack before the main attack, then that would make a huge a difference. It would mean that the Normandy beachhead could be established. So it was a sort of a poker game they were playing. … a game of massive bluff.

“One of the most bizarre aspects of this whole story was the decision to make a fake Monty. They found a half-out-of-work Australian actor who looked a bit like [Montgomery, who commanded the Allied ground forces during D-Day]. The problem with him is that he had lost a finger during the first world war, so they gave him a fake finger and trained him up to speak like Monty and to look like Monty. And they made sure that he was spotted somewhere other than the disembarkation grounds in Britain just before the D-Day invasion.”

Despite a last-minute fear that the plans for Operation Overlord had been exposed in the answers to a crossword in a national London newspaper, which included the answers “Utah” and “Overlord,” this massive bluff was completely successful, allowing the Allies to invade Europe in a spot not anticipated by the Nazi high command.  Just over two months later, Paris was returned to Allied hands on 25 August 1944, and eight months later Germany surrendered on V-E day, 8 May 1945, and the war, at least in Europe, was over.