Eisenhower .
The general plan for the invasion of Europe by the allies.
Well, operation "overload" was very helpful, but FDR died before the end of the war.
the invasion of German occupied Europe at Normandy, France, June 6, 1944
After World War 2
Operation Weserubung.
Operation Overlord was the D-Day attack at Normandy.
Operation Barbarossa
The operation let the Allies win world war!
Operation Frühlingserwachen
It was fake it isn't real
It wasn't a war, it was an operation during World War 2. Operation Barbarossa was the codename for the German invasion of Soviet Russia in 1941. Pretty decisive stuff.