This operation will always be known as one that helped to turn the tide of human history. How much do you know about World War II's Operation Overlord?
For years, the Allies were staggered by the Nazi war hammer. With Operation Overlord, they initiated what they hoped would be a successful push against the Germans on the western front.
Operation Overlord began on June 6, 1944. It all started with a more specific operation, called Operation Nepture, which became the linchpin for a successful attack.
The operation was planned to unfold in stages, and it began with an aerial assault. Tens of thousands of paratroopers were dropped behind enemy lines to make way for the coming amphibious assault.
Hitler was anxious that the Allies would find a weak point along the Atlantic Wall, so he really wanted about 300,000 troops guarding fortifications. But the Germans simply didn't have enough men and supplies to meet Hitler's unrealistic standards.
The Germans knew that an attack was imminent, and they prepared accordingly. However, they weren't sure exactly where the attack would take place, meaning there was some uncertainty about how to allocate their defenses.
Dwight Eisenhower was the top military leader for Allied forces, and he penned a few timeless lines to his men before they began their perilous expedition. He also wrote, "The hopes and prayers of liberty-loving people everywhere march with you."
The Allies picked five landing points on the beaches of Normandy. To attack those points, they called upon about 160,000 men, many of whom didn't even make it to shore, victims of German fire or drowing.
Hatchet wasn't one of the sectors. Those now-famous sectors were named Omaha, Utah, Sword, Juno and Gold. By the end of D-Day, those sectors were awash in Allied blood.
The Canadians were ordered to take Juno beach. Before the attack, Canadians leaders feared that they might suffer as many as 2,000 casualties. In the end, they endured about 800 casualties, with about 350 dead.
Nearly 7,000 vessels took part in the initial invasion of Normandy. Even from the high vantage point of a bomber, the boats and ships stretched as far as the eye could see.
The troops making up the Omaha beach landings were mostly Americans, who faced the unfortunate circumstance of wading into the worst of the Nazi defenses. Roughly 2,000 men died on the beach in a scene that fell nearly into chaos.
Due to years of combat, the Nazi ranks were already depleted when Overlord began. The Germans had burned through their supply of young men, meaning that on average, Nazi soldiers were nearly six years older than Allied troops.
German guns were pre-sighted for the beaches when the Allies landed, meaning that many soldiers never had a chance at survival. More than 4,400 perished, and there were roughly 10,000 total casualties.
The "D" moniker has been used for numerous campaigns in history, but it's now most closely associated with World War II. It simply denoted the day that military operations began in Normandy.
Operation Bodyguard was a misinformation campaign conducted by the Allies in the months leading up to D-Day. The Allies issued many false radio transmissions to confuse the Germans regarding the date and location of the invasion.
Most of the troops that hit the beach running on D-Day were British. They numbered about 83,000 when combined with Canadian soliders. American troops number around 73,000.
The Mulberry harbors were portable, temporary harbors designed to help the Allies quickly move cargo and men ashore. The harbors were towed across the English Channel and into position following the invasion. They were used for months after the invasion because Normandy's natural harbors were still heavily defended by the Nazis.
Exercise Tiger was top-secret, but the Germans found a way to attack the ships as they gathered for a practice run. They conducted a surprise raid and killed more than 700 Allied sailors. Because the exercise was classfied, there was virtually no media coverage.
Sadly, as many as 20,000 French civilians were killed on D-Day, most of them victims of Allied bombs meant to clear the way for invasion forces.
Once the Allies finally gained a foothold in Western Europe, they weren't going to give up ground. They pumped in supplies and reinforcements, until there were more than 2 million troops in the area.
"Bigot" was a codename for officers who knew the plan to land troops in Western Europe. These so-called Bigots were never allowed near Germans, for fear they'd be captured and reveal details about the Allied invasion.
There were thick, low clouds on June 6 that made it difficult for bombers to pick out targets on the coastline. As a result, many failed to damage German defenses, meaning that Allied troops wandered right into the teeth of Nazi guns.
The invasion of Normandy was treated as a top-secret operation. Most Allied troops weren't told where they were going until they began moving across the English Channel towards France.
The full power of the Allies was at hand on D-Day, when nearly 11,600 aircraft took to the skies against Germany. They flew nearly 15,000 sorties that day.
Given the immensity of the situation, Allied aircraft losses were fairly low on D-Day. They lost only 127 planes out of more than 11,000 that flew missions that day.
The Allies faced immense fortifications as they stormed the Atlantic Wall … but most of the invasion force cleared the wall in just hours. The steel used in the Wall might've been better used to build about 20,000 Tiger tanks.
Shortly after midnight, British airborne soldiers swooped into France using gliders. They successfully secured two bridges that were critical to the invasion forces.
Operation Overlord was a resounding success, but it came with a high casualty rate. There were nearly 210,000 Allied casualties, and in that number around 37,000 dead.
Nearly a million French people were forced to build Hitler's Atlantic Wall, which stretched along more than 1,600 miles of coastline. Concrete was used to create many of the fortifications, many of which are still intact.
After years of Nazi domination in Europe, Operation Overlord proved to be a major turning point in the war. Just 11 months later, the Allies captured Berlin and Hitler committed suicide, ending one of the bloodiest eras in human history.