World War II is the defining conflict of the 20th century, one that created a line in the sands of history dividing the pre-war and post-war eras. In this epoch-defining conflict lies another definitive moment: the invasion of a 50-mile stretch of coast in Normandy, France, on June 6, 1944. This battle, also known as D-Day, was the pivot point of the war in Europe. Its success led to a nearly yearlong, bloody campaign that saw the liberation of France, Luxembourg, Belgium, and the Netherlands, followed by the final defeat of Hitler’s Third Reich.

In the six lectures of D-Day Revisited: The Invasion of Normandy, Professor John C. McManus will take you back to this transformative moment in modern history and reveal how it succeeded. Along the way, you will better understand why it was a truly world-changing military operation—one that could easily have gone a different way.

The invasion of Normandy was a team effort, and the alliances forged to ensure its success would lead to the creation of NATO, which in turn would shape the geopolitical landscape of the post-war world. To truly get a full picture of D-Day, you will examine the painstaking planning of the Allied forces, as well as the difficulties presented by high winds, dense clouds, difficult terrain, and other factors that almost created a very different outcome.

Though successful, D-Day bore a heavy cost. With some 10,000 Allied casualties, including 2,501 American fatalities, June 6 was the deadliest day in World War II for the United States. As you reexamine this battle, you will see why we continue to remember D-Day not only for its crucial role in the defeat of the Nazi regime, but also for the immense sacrifices made to secure democracy in Europe.