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Today In History


Jun-05, 2016

What Does D-in-Day Mean?

The terms D-Day and H-Hour are used for the day and hour on which a battle or operation is to be initiated.  These terms are designated for day and hour for an operation when the actual day and hour have not yet been determined or announced. When used in combination with figures and plus or minus signs, these terms indicate the length of time prior or following a specific action. Thus, H-3 means 3 hours before H-hour, and D+3 means 3 days after D-day. H+75 minutes means H-hour plus 1 hour and 15 minutes.

As per the United States Army's Center of Military History, the initially known use of these terms is in Field Order Number 9, First Army, and American Expeditionary Forces. It is actually dated September 7, 1918: "The first Army will attack at H hour on D day with the object of forcing the migration of the St. Mihiel Salient." D-Day for the invasion of Normandy was set for June 5, 1944, but it actually occurred on June 6. Thus, D-Day, as it applies to Overlord, is June 6, 1944.


The Operation Overload

It is hard to imagine the epic scope of this vital battle that shadowed out the dream of Hitler’s Nazi domination.  On June 6, 1944, more than 160,000 Allied troops landed along with a 50- mile stretch of heavily- prepared French coastline, to fight the Nazi domination on the beaches of Normandy, France. Gen. Dwight D. Eisenhower called this battle a cause in which, “we will accept nothing less than full victory."

More than 5,000 Ships and 13,000 aircraft supported the D-Day attack, and by day’s end, the Allies gained a foot-hold in Continental Europe. The cost in lives on D-Day was very high as 9,000 and more Allied Soldiers were killed and wounded, but their sacrifice allowed 100,000 more Soldiers to begin the slow, hard plod across Europe, to defeat Adolf Hitler’s crack troops. But the battle for Normandy was far from over.

Return to Normandy

Twenty days into the operational overload the Allies had advanced only a dozen miles inland. But by July, the getaway from Normandy had begun. Troops fought the battle among the fields and captured St. Lo; by month’s end, the troops were at the edge of Brittany. By August, Brittany was in Allied hands, and it was on to Paris, which was liberated on Aug. 25. However, the Allied advance suffered a hold-up in the Netherlands during Operation Market Garden and caught up in December at the legendary Battle of the Bulge.

On March 7, 1945, the U.S. 9th Armored Division captured the bridge at Remagen, Germany, and by that month’s end all of the Rhine was in Allied hands, then the march across Germany had begun. Just a little more than eleven months later on May 9, 1945, after the D-Day, the Nazis surrendered.

Now, seven decades later, renowned by still-thankful French residents, the D-Day veterans, along with their families and friends, and with tourists will go to the invasion beaches of Utah, Omaha, Gold, Juno and Sword to commemorate the Allies’ efforts and sacrifices.

The D-Day Invasion

D-Day in the United States is observed in memory of the Normandy landings in France on June 6, 1944, the battle in which American soldiers and other Allied forces fought to end World War II in Europe.

Public Life

The D-Day is an observance and not a federal holiday in the United States.

What Do People Do?

On this day, people visit to some museums and war memorials which host exhibitions featuring photos and film as an honor to soldiers who were part of the Normandy landings. D-Day memorials and ceremonies are also held to memorize these soldiers.

The first assault groups to land on D-Day at Omaha Beach was the Company E, 16th Infantry, 1st Infantry Division.; Center for Military History, U.S. Army. U.S. Army.