III.

Preparations for D-Day

Britain and the United States agreed that the supreme commander for the invasion would be an American, and Roosevelt chose U.S. Army general Dwight D. Eisenhower. The Allied ground forces commander for the D-Day invasion, which was code named Operation Overlord, was British general Bernard Montgomery. The broad outline of the attack was relatively simple: find suitable beaches, gather a landing force, isolate the battlefield by attacking bridges, tunnels, and rail networks so that the German defenders could not be easily reinforced, and land the troops. Once a beachhead was established, the plan was to pour in the supplies needed to sustain an offensive and then break out into the French countryside. Executing the plan was not so simple. Crossing the treacherous English Channel with its unexpected storms, enormous tides, and tricky currents would be just the first step of the amphibious assault.

The attack on Fortress Europe, as it was known, required the utmost secrecy. The assembling force was isolated in southern England to prevent details of the plan from leaking out, and deceptive measures were taken to mislead the Germans about the intended landing site. The deceptive measures included phony tanks and landing craft, some made of cardboard, plywood, or rubber, and a dummy oil tank farm near Dover, the English town closest to the European mainland and just opposite the city of Calais, France. This elaborate effort was intended to make the Germans believe that the invasion would come from Dover. The effort was so successful that Germany kept its main forces in the Pas-de-Calais region even after the invasion took place, as Hitler feared that the Normandy invasion was only a feint and the main invasion was yet to come.

The Allied planners focused on the beaches around Caen and the Cotentin Peninsula in northern France rather than those of Calais, even though it meant the force would be crossing at a wider part of the English Channel. That disadvantage was far outweighed by what the site offered: comparatively scanty defensive fortifications and beachhead ideally suited for successful exits. The clincher was an isolated battlefield that the Germans would have difficulty reinforcing.

The date was set for May 1, 1944, to allow for a dawn invasion at low tide, when beach obstacles that could impede the landing craft would be visible. But it soon became apparent that the May 1 date would find the Allies still short of the landing craft necessary to mount the great invasion. Reluctantly, Eisenhower reset D-Day to the next suitable date—June 5, 1944. The force continued to assemble as British, Canadian, and American soldiers flooded into southern England. The Allies planned to put 5 divisions on the beaches for an initial assault against a defending German force of 50 infantry and 11 armored divisions stationed in France. The average German division had about 10,000 soldiers.