In late 1943 President Franklin Roosevelt appointed Eisenhower to serve as the Supreme Allied Commander in the European Theater of Operations. Eisenhower assumed responsibility for the invasion of Western Europe; Operation Overlord. His directive from the Combined Chiefs of Staff read, “You will enter the continent of Europe and in conjunction with other Allied nations, undertake operations aimed at the heart of Germany and the destruction of her armed forces…”
After establishing his headquarters outside London in January 1944, Eisenhower set about preparing his forces for the invasion. Normandy France, across the English Channel, was chosen for the invasion’s landing site.
At about 9:30 p.m. (21:30 hours) on the evening of June 4, 1944, Eisenhower called a meeting at his command post at Southwick House in Portsmouth, England. A storm with high winds and rain had forced a one-day postponement of the invasion, originally set for June 5. Eisenhower had learned from his meteorological staff that there would be a break in the weather and that the next day, Tuesday June 6, would be more favorable. He considered all the variables. General Montgomery, his ground commander, favored taking the risk. After a long silence, Eisenhower gave the command, "Okay, we'll go." It was the most important decision in his military career.
Once the order for the invasion was given, the Supreme Allied Commander could only wait until the results came in. It was up to the troops to decide the out-come.