Primary Image: Soldiers coming ashore at Normandy on D-Day. (Image: National Archives and Records Administration, 111-SC-320902.)

In May 1944, the Western Allies were finally prepared to deliver their greatest blow of the war, the long-delayed, cross-channel invasion of northern France, code-named Overlord. General Dwight D. Eisenhower was supreme commander of the operation that ultimately involved the coordinated efforts of 12 nations.

After much deliberation, it was decided that the landings would take place on the long, sloping beaches of Normandy. There, the Allies would have the element of surprise. The German high command expected the attack to come in the Pas de Calais region, north of the river Seine where the English Channel is narrowest. It was here that Adolf Hitler had put the bulk of his panzer divisions after being tipped off by Allied undercover agents posing as German sympathizers that the invasion would take place in the Pas de Calais.

Surprise was an essential element of the Allied invasion plan. If the Germans had known where and when the Allies were coming they would have hurled them back into the sea with the 55 divisions they had in France. The invaders would have been on the offensive with a 10-to-1 manpower ratio against them.

The challenges of mounting a successful landing were daunting. The English Channel was notorious for its rough seas and unpredictable weather, and the enemy had spent months constructing the Atlantic Wall, a 2,400-mile line of obstacles. This defensive wall comprised 6.5 million mines, thousands of concrete bunkers and pillboxes containing heavy and fast-firing artillery, tens of thousands of tank ditches, and other formidable beach obstacles. And the German army would be dug in on the cliffs overlooking the American landing beaches.

At the Tehran Conference in August 1943, Allied leaders scheduled Overlord to take place on or about May 1, 1944. In the meantime, they prepared ceaselessly for the attack. Trucks, tanks, and tens of thousands of troops poured into England. “We were getting ready for one of the biggest adventures of our lives,” an American sergeant said. “We couldn’t wait.” Meanwhile, the American and British air forces in England conducted a tremendous bombing campaign that targeted railroad bridges and roadways in northern France to prevent the Germans from bringing in reserves to stop the invasion.

Allied leaders set June 5, 1944, as the invasion’s D-Day. But on the morning of June 4, foul weather over the English Channel forced Eisenhower to postpone the attack for 24 hours. The delay was unnerving for soldiers, sailors, and airmen, but when meteorologists forecast a brief window of clearer weather over the channel on June 6, Eisenhower made the decision to go. It was one of the gutsiest decisions of the war.

Just after midnight on June 6, Allied airborne troops began dropping behind enemy lines. Their job was to blow up bridges, sabotage railroad lines, and take other measures to prevent the enemy from rushing reinforcements to the invasion beaches. Hours later, the largest amphibious landing force ever assembled began moving through the storm-tossed waters toward the beaches. Most of the Americans were packed into flat-bottomed Higgins boats launched from troop transports 10 miles from the French coastline. Vomit filled the bottom of the boats, and as water kept rushing in over the gunwales, the green-faced men had to bail this vile stew with their helmets. Though it was cold, the men were sweating.

Planners had divided the landing zone into five separate beaches. The British and Canadians landed at Juno, Gold, and Sword beaches. The Americans landed at Omaha and Utah beaches.

The fiercest fighting was on Omaha Beach where the enemy was positioned on steep cliffs that commanded the long, flat shoreline. Troops leapt from their landing boats and were pinned down for hours by murderous machine-gun fire that turned the beach into a vast killing field. “If you (stayed) there you were going to die,” Lieutenant Colonel Bill Friedman said. “We just had to . . . try to get to the bottom of the cliffs on which the Germans had mounted their defenses.” By midday, the Americans had surmounted the cliffs and taken Omaha Beach at a heavy cost: over 4,700 killed, wounded, or missing out of the total of approximately 35,000 who came ashore that day, a loss rate of more than 13 percent.

By nightfall, about 175,000 Allied troops and 50,000 vehicles were ashore with nearly a million more men on the way that summer.

The Normandy invasion was one of great turning points of 20th-century history. An immense army was placed in Nazi-occupied Europe, never to be dislodged. Germany was threatened that same month by a tremendous Soviet invasion from the east that would reach the gates of Berlin by the following April. The way to appreciate D-Day’s importance is to contemplate what would have happened if it had failed. Another landing would not have been possible for at least a year. This would have given Hitler time to strengthen the Atlantic Wall, harass England with the newly developed V-1 flying bombs and V-2 rockets, continue to develop jet aircraft and other so-called “miracle weapons,” and finish off his killing campaign against ethnic and sexual undesirables.