– Nick Hewitt is a historian in the Department of Research and Information at the Imperial War Museum in London. He studied history at Lancaster University and War Studies at King’s College, University of London, where he specialised in naval history. He joined the Imperial War Museum in 1995. The opinions expresed are his own.-“D-Day at last! Invasion! Hurrah! God save the King!” wrote a Cheshire schoolgirl on the evening of 6 June 1944. For her, news of the successful D-Day landings clearly meant a great deal. But looking back after sixty-five years, what was the historical significance of D-Day?In purely military terms, it is almost impossible to exaggerate the importance of this extraordinary operation. Operation “Overlord” was the result of four years of hard-won experience, painstakingly acquired from the early commando raids, and then from amphibious operations of steadily increasing scale and complexity in the Mediterranean. By June 1944, the Allied sea, air and land forces were at a peak of efficiency and strength, but it had been a long, hard road.”Overlord” was probably the most ambitious military operation in history. It involved putting ashore on one day around 133,000 men and as many as 10,000 vehicles along 50 miles of defended coastline, from more than 4,000 landing craft. A wealth of ingenious equipment had been developed, from new helmets, to swimming tanks and the “Mulberry” artificial harbours.Over 1,200 naval warships defended the invasion fleet, and more than 23,000 airborne troops landed in support. (In comparison, the landings at San Carlos Bay during the 1982 Falklands War involved just 4,000 men and four assault ships.) And it is important to remember that amphibious assault landings were and remain by far the riskiest of all military operations. Field Marshal Sir Alan Brooke, Britain’s Chief of the Imperial General Staff, wrote on 5 June that ‘it may well be the most ghastly disaster of the entire war. I wish to God it were safely over.’ Hindsight teaches us that D-Day was a great success, but at the time it was seen by many as an enormous gamble, a dramatic throw of the dice on which the highest of stakes rested.For the people of Europe, D-Day meant liberation from four long years of occupation and oppression. For the British it meant a triumphant return to France, from which they had been humiliatingly evicted in June 1940. Senior American planners congratulated themselves that their confident preference for a direct assault across the Channel had been vindicated; the British, equally, congratulated themselves on delaying the operation until the time was right – had D-Day taken place in 1943 or even 1942, as some Americans wanted, the outcome would probably have been very different.Since the war, the historical significance of D-Day has been cemented and, arguably, distorted by its position in popular culture. Its anniversary is always marked, perhaps at the expense of anniversaries from other campaigns, sometimes to the distress of veterans from these further-flung battlefields. Who, now, remembers that Rome fell the day before D-Day?In Britain, we tend to focus on the distortion caused by American movies like Saving Private Ryan, when they fail to recognise British involvement, but for our part, we should remember that the bulk of the German Army was defeated in the east by Soviet forces, not by the western Allies. D-Day was an important element of a global effort made by millions of people from an unprecedented international coalition. D-Day alone did not bring about the defeat of Nazi Germany.Nevertheless, it was an operation of unprecedented scale, ingenuity, complexity and risk. Above all, it was a success. In forcing Germany to fight a two front war against, for the first time, the full combined weight of the United States, Great Britain and the Soviet Union, it was perhaps the tipping point that made the final collapse of the Third Reich inevitable.