Talking About World War II: Why did General Eisenhower choose Normandy for Operation Overlord?

When Gen. Dwight D. Eisenhower arrived in London from the Mediterranean Theater of Operations in January of 1944 to take command of the Allied Expeditionary Force and carry out Operation Overlord, the site of the invasion - Normandy - had already been selected.

Planning for an eventual invasion of France was already well underway by January 15, 1944; before Eisenhower was selected as Supreme Commander, Allied Expeditionary Force, Lt. Gen. Frederick Morgan of the British Army had already crafted a preliminary invasion plan under his title of presumptive Chief of Staff, Supreme Allied Commander (Designate), or COSSAC.

After taking the COSSAC assignment in March of 1943, Morgan and his planning staff looked at their maps of occupied Northwest Europe in search of possible landing sites on the northern coast of France, the likeliest target for an invasion due to its proximity to Britain and its southern ports of embarkation.

The Pas de Calais was ruled out almost right away even though it is the point at which France is closest to Great Britain - 20 land miles, 18 nautical miles at the Dover Narrows. The Allied invasion fleet would have had a shorter transit from Britain to Occupied France, and it could have sailed under continuous air cover by the Royal Air Force and the U.S. Army Air Forces based in Kent, East Anglia, and Southern England. However, because Calais and all of the Channel ports nearby, including Dunkirk, were also closer to Germany, that’s where Adolf Hitler and his generals expected the invasion to take place. Correspondingly, the strongest German army in France, the Fifteenth, was stationed mostly in the Pas-de-Calais, with only a few divisions spilling over into Normandy itself west of the Seine.

The Brittany Peninsula that juts out into the Atlantic at the far western stretch of the English Channel to the south of Normandy was also briefly considered, but it was too far out of the range of a Spitfire fighter - the default setting, one might say, for Allied air forces’ ability to provide continuous air cover, especially in daylight. It was also farthest away from British ports, and perilously close to U-boat bases on France’s Atlantic Coast.

Morgan and his Anglo-American staff decided on Normandy because:

• It was still within range of most Allied single-engine fighters and their bases
• It was in range of the Air Transport Command bases for the airborne phase of Overlord
• It was farther away from England (and the German western border), but it had ample beaches and was near two suitable ports (Cherbourg and Le Havre)
• It was less fortified than the “likelier” invasion site, the Dover Narrows, and Rommel’s Army Group B had garrisoned the region with the smaller Seventh Army

The initial Overlord plan, incidentally, called for a modestly-sized initial landing force of three divisions on a narrow front in the Bay of the Seine area and several airborne drops to secure the flanks. Morgan and his staff also advocated the use of artificial harbors - the Mulberries - to compensate for the lack of a port until Cherbourg or Le Havre were liberated and made ready for Allied shipping. COSSAC based this - and a conditional May 1, 1944 date for D-Day - on the amount of assault shipping - especially the number of landing craft - the staff assumed would be available for the invasion. With the Allies also involved in naval operations in the Mediterranean, the Pacific, and other theaters, demand for shipping, especially for the crucial Landing Ship Tank (LST), exceeded supply.

When Eisenhower and his chosen commanders arrived in London less than five months before D-Day, they evaluated Morgan’s plan for Overlord. Gen. Bernard L. Montgomery, the British commander of 21 Army Group, the force that would carry out the initial phases of the operation, was not satisfied with the existing scheme. He agreed with the basic principle of securing a beachhead, then creating a lodgement area inland before breaking out into open country and heading for Paris, the Channel ports, and then the German frontier. But Monty quickly saw that the initial landing force was too small, the landing area too narrow, and that another beach was needed closer to Cherbourg. He revised the plan so that there would be five invasion beaches, including one at the low end of the Cotentin Peninsula, and increased the number of divisions in the first landings from three to five, with three airborne divisions dropped the night before D-Day to secure the exposed flanks of the Overlord landing zones.

Eisenhower approved Montgomery’s revisions to Morgan’s Overlord plan. So did Ike’s superiors, the Combined Chiefs of Staff, or (as Eisenhower referred to them) the Charlie Charlies. The larger invasion force would give Overlord better odds of success, and although Normandy is further away from Britain, the Allies would not have to worry about being beyond friendly air cover or being too far away from the British ports from which the Allied armies would draw their sustenance.

The only downside was that a larger landing force would require more landing craft, especially of the shallow draft LST types. Some could be recalled from the Mediterranean, which would result in the postponement of Operation Anvil, a landing in Southern France that was also originally scheduled to take place simultaneously with Overlord. Additionally, several LSTs that were slated for Overlord had been lost in Operation Shingle, the landing at Anzio that took place on January 22, 1944, a week after Eisenhower and his battle captains arrived in London. Eisenhower requested a postponement of D-Day from May 1 to June 1 to allow for a month’s production of more landing craft