D-Day...The amphibious assault that left the Nazis on their knees

As with many military victories, 75 years on, D-Day remains an uncomfortable mixture of triumph and tragedy. On the one hand, it was a testament to the courage and fortitude of Allied soldiers, and a major step towards overthrowing Hitler and ending the Holocaust. On the other, thousands of men lost their lives by breakfast, and the channel ran red with British, American and Canadian blood.

Certainly, D-Day is a pivotal, poignant and all-too-recent event that must be remembered. Here, we talk to World War II historian and broadcaster James Holland - to commemorate, celebrate and, most of all, re-evaluate this crucial moment in our history.

Operation Overlord

We're guessing most of you are familiar with the D-Day story, but for those that slept through history class, here's a quick recap. At 6.30 on the morning of June 6, 1944, Allied forces began landing at five main locations along the Normandy coastline, raising the curtain on World War II's final act. In answer to the perennial pub quiz question, the beaches were code-named Omaha, Juno, Utah, Sword, and Gold.

The Allies had already pummelled high-value targets with a coordinated bombing campaign, pounded coastal positions with artillery, and by cover of night dropped 18,000 paratroopers behind enemy lines.

What followed was the largest amphibious invasion of all time, and thanks to a prolonged intelligence effort it caught the Germans off-guard. Operation Fortitude - as this web of deception was known - convinced Hitler's generals that the Normandy landings were a mere sideshow, covering for the real invasion near Calais. So wholly were they fooled,that on the fateful morning, no one bothered to wake Hitler for several hours, and when they did he showed little concern. Field Marshal Rommel had just returned from celebrating his wife's birthday, and his chief of staff had stayed up half the night drinking.

Despite heavy machine gunfire and appalling weather, Allied troops swarmed the depleted defences, and successfully established beachheads. By the end of the day, around 156,000 Allied soldiers had landed in Nazi-occupied France.

A logistical triumph

None of this is contested, but the details of D-Day - how it happened, how it should have happened, who gets the credit/blame - are furiously debated to this day.

D-Day was a moment of unparalleled human drama which still captures hearts and minds, so it sometimes receives unwarranted emphasis. "It's one day of 77 in the Normandy Campaign," says Holland, "and you can convincingly argue that the Battle of Normandy begins 12 weeks earlier with the air battle. It's important not to get stuck on D-Day."

Previous narratives, he suggests, have zoned in on the strategic and tactical - the military objectives and minute-by-minute manoeuvres - while neglecting the nuts and bolts of war like supplies, factories and shipping.

"Once you insert that operational level," he says, "you realise the Allies are fighting Big War - capital B, capital W. They're fighting by air, land and sea, with an enormously long support tail." The German army had supposed advantages, but the Allied MO was more attuned to the needs of a long-term war effort.

"People say German equipment was brilliant and ours was rubbish," says Holland. "Well, let's break it down a bit. If you're a young soldier up against a Tiger tank - huge, scary, with big tracks, big guns, lots of armour and black-jacketed SS types - you'd be thinking, 'I don't fancy that'."

"But what the private in his fox hole doesn't appreciate is that the tank is an unbelievably complex piece of kit that's very likely to break down, requires huge amounts of fuel which the Germans don't have, and an even bigger support chain. The Allied Sherman tank may not have the guns or the armour, but it's lighter, fits on a landing ship, fires more quickly and accurately on the move, and is much easier to maintain in the field.

"People go on about how our tanks couldn't compete with a Tiger or a Panzer, but we had vast numbers of anti-tank guns that did, and the number of tank-on-tank engagements was incredibly small."

It's the same story for the Allied commanders, chief among them the stupendously vain and heroically unlikable General Montgomery. Something of a pantomime villain, when asked to name three great generals, he replied: "The other two would be Alexander the Great and Napoleon."

"Montgomery has been massively criticised," says Holland, "but if you actually look at his generalship rather than what he's like as a bloke, he comes across much better. There's not a single commander that had any quibbles with his plan beforehand - it was the best they had with the resources that were available."

As for the Germans, Holland reckons we've been a little overawed. "It's all very well having a bit of cut and dash in your tiger tank, but they couldn't organise a p*ss-up in a brewery."

Our finest hour?

If there's one thing historians love doing, it's re-framing established narratives, and the triumphalism of the Allied victory was ripe for revisionism in the Seventies and Eighties.

Holland is keen to re-revise it back: "There's this self-flagellation among British historians," he says, "they can't resist the urge to do down the British effort. There's post-empire guilt, the decline of Britain as a power, the three-day week - and then it becomes a bandwagon."

Holland argues that, if the Battle of Britain was the UK's 'finest hour', D-Day isn't too far behind. "It was an amazing achievement," he says. "The level of co-ordination was astonishing and the logistics will make your head throb. There's a real commitment among the Allies, in stark contrast to the Germans who are fighting among themselves."

As for the American view, there's a tendency to assume that "little Britain" could not have played a leading role. The data suggests otherwise: Of the 1213 warships involved, 892 were British, as were all three service chiefs and two-thirds of participating aircraft. Two-thirds of the troops were British and Canadian, and British boats made up 3,613 of the 4,127 landing craft.

"People assume that Omaha Beach is D-Day, and that it was won by the Americans," says Holland. "But Omaha Beach is all over by nine o'clock in the morning. What the Americans did was amazing, but it's wrong to suggest that D-Day was an American show."

Appraising Private Ryan

If there is one thing that's shaped public perception of D-Day, besides dormant memories of school curricula, it is Saving Private Ryan. The 1998 film opens with the American landing at Omaha, and has been widely lauded for communicating the chaotic, unspeakable terror of war. Men trembling in puddles of their own vomit, shell-shocked soldiers searching for lost limbs, the muffled screams of the injured drowning in the incoming tide.

For historians, this isn't exactly wrong - more faintly misleading. "Saving Private Ryan shows what it was like at a couple of points for a very short period of time," says Holland. "Some initial sorties were hammered, but most landings were fine."

"If you look at the after-action reports, some companies say 'crossed the beach, one casualty', or 'crossed the beach, no casualties'. Even Omaha Beach was not as bloody as Saving Private Ryan. The total dead was 842 - a huge number, but I suspect most would have guessed closer to 2,000 or 3,000."

Holland's overall take is simple: When you analyse D-Day in its broader contexts, the Allies look better and the Germans look worse.

"Things never go 100% to plan," he says. "But the landings were a success, the flanks were secured, and the Allies weren't kicked back into the sea. By anyone's reckoning that was a pretty good result."

Normandy '44: D-Day And The Battle For France by James Holland is published by Bantam Press, priced £25. Available now.