Who Operation overlord?

Answer 1

No one "wins" operations. Operation Overlord was an Allied offensive, only they knew about it and so only they called it Ovelord. An operation fails or it succeeds. Battles or campaigns are won, not operations. But in terms of the Invasion of Normandy, I think it's fairly obvious that the Allies won. If the invasion had not been successful, we wouldn't have had a war in the Western theater, and all of Europe would have been plunged into communist rule; we wouldn't have had 10,000 movies about D-Day itself and then later about Americans fighting in Europe (Band of Brothers, Saving Private Ryan, The Longest Day, etc); we wouldn't remember June 6th as the anniversary of D-Day; civilians probably wouldn't even be familiar with the term D-Day; and there probably wouldn't be a huge American cemetery in Normandy commemorating the sacrifices of the men who died in the invasion.