Why Is It Called D-Day, Anyway?

Illustration for article titled Why Is It Called D-Day, Anyway?

Today marks the 71st anniversary of the Allied invasion of Normandy, France, designated at the time as Operation Neptune but known in popular culture today as D-Day. Why is that, and what does the D stand for?


Lots of people think it means “Decision Day,” “Doomsday” or even “Death Day.” And considering the massive casualties experienced on both sides that day and during the Operation Overlord campaign that followed, those things all make sense.

Despite a lot of disagreement among military historians, according to the U.S. Army itself and the National World War II Museum, the D probably just stands for Day. No, not “Day Day,” but rather a sort of measurement of time:

This coded designation was used for the day of any important invasion or military operation. For military planners (and later historians), the days before and after a D-Day were indicated using plus and minus signs: D-4 meant four days before a D-Day, while D+7 meant seven days after a D-Day.


So it’s not the “D” that matters in D-Day, but rather the “Day,” which designates the actual date of the event itself.

But as I mentioned, not everyone agrees with this. Even the French and one of Eisenhower’s own generals had different explanations:

Many explanations have been given for the meaning of D-Day, June 6, 1944, the day the Allies invaded Normandy from England during World War II. The Army has said that it is “simply an alliteration, as in H-Hour.” Others say the first D in the word also stands for “day,” the term a code designation. The French maintain the D means “disembarkation,” still others say “debarkation,” and the more poetic insist D-Day is short for “day of decision.” When someone wrote to General Eisenhower in 1964 asking for an explanation, his executive assistant Brigadier General Robert Schultz answered: “General Eisenhower asked me to respond to your letter. Be advised that any amphibious operation has a ‘departed date’; therefore the shortened term ‘D-Day’ is used.”

Luckily, VE-Day and VJ-Day are a heck of a lot easier to figure out.

Photo credit Getty Images

Contact the author at patrick@jalopnik.com.

Share This Story

Get our newsletter



Ike was President from 1953-1961, so I doubt anyone would have been referring to him as General Eisenhower in 1964 or even 1954, nor would inquiries to him be answered by a military officer then. So the date of the anecdote at least is wrong. Eisenhower also never wore his military unifom while President as he felt it was important to keep the office separate from the military, and warned against the dangers of the military exerting too much influence over the government. There really should be a moment of silence in this country every June 6 for all those who fought on that day each year and didn’t come home, or who have perished since, or are still alive and should know we still remember or have learned of their sacrifices and are grateful.