Operation Overlord was the code-name given to the Allied invasion of France scheduled for June 1944. The overall commander of Operation Overlord was General Dwight Eisenhower. Other senior commanders for Overlord included Air Marshall Leigh-Mallory, Air Marshall Tedder, Field Marshall Bernard Montgomery and Admiral Bertram Ramsey. Operation Overlord required the type of logistical issues that no army had ever had to cope with before and the plan was for the Allies to have landed a vast amount of both men and equipment by the end of D-Day itself.
The command team for D-Day
Overlord itself required the involvement of many men – both in Britain and in France via the Resistance. Security for the plan had to be total. The fact that the Germans were taken by surprise at Normandy indicates that the Allies were successful in this.
The first issue that the Allies had to decide on was where to land in France. The Pays de Calais was an obvious choice as it was the nearest part of France to Britain. Getting to France would be swifter but the whole area was known to be well defended.
The Allied high command decided on a landing in Normandy. The risks were much higher but the beaches were suitable for a mass landing of people and equipment. A diversionary attack on Calais was considered in an effort to confuse the Germans.
One of the first plans was known as the COSSAC (Combined Anglo-American) plan. This included a plan to use two airborne brigades to protect the flanks of the three landings in Normandy.
Montgomery added an amendment to the COSSAC plan. He wanted an attack on five beaches in Normandy with support given to the amphibious landings by two airborne divisions landing on the flanks of the beach attacks in the vicinity of Caen and in the southeast corner of the Cotentin Peninsula. Montgomery wanted a beach assigned to a specific army from either Britain or America – he did not envisage a joint force landing on each beach.
Eisenhower backed Montgomery’s plan and the final variant of Overlord was very similar to Montgomery’s plan. Whereas Montgomery had bargained for five divisions to be landed, Eisenhower had a desire to land more men – 18 divisions by D-Day plus 10.
The planning and logistics behind Overlord were unparalleled in history. The Allies had to ensure that none of the plan was released – above all, the desire to fool the Germans that the Pays de Calais was the main target as opposed to Normandy.
The mere gathering of equipment needed for the invasion was an issue in itself. Where could it be stored without attracting the attention of German spies? How could it be transported to selected places in the south without local people talking about it? How could the thousand of boats needed for the invasion be gathered together and readied?
For the actual invasion, 6,000 ships were needed for D-Day and for future cross-Channel trips carrying troops and equipment. In the first three days of the attack, Overlord planned to move over 100,000 men and nearly 13,000 vehicles. The plan also included the movement of an artificial harbour so that people and materials could be landed with more ease once the landing beaches had been secured..
Overlord had built into it the movement of a total of 3 million men in 47 divisions, moved by 6000 ships with aerial cover provided by 5000 fighter planes. That it was such an overwhelming success (with major casualties only occurring at Juno and Omaha Beach) is indicative of how well planned it was.