In December 1943, President Roosevelt decided that Eisenhower – not Marshall – would be Supreme Allied Commander in Europe. The following month, he resumed command of ETOUSA and the following month was officially designated as the Supreme Allied Commander of the Allied Expeditionary Force (SHAEF), serving in a dual role until the end of hostilities in Europe in May 1945. He was charged in these positions with planning and carrying out the Allied assault on the coast of Normandy in June 1944 under the code name Operation Overlord, the liberation of Western Europe and the invasion of Germany.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): What was the Allied invasion of Normandy called?
Operation Overlord