D-Day was one of the major events of World War Two. D-Day saw a vast Allied armada deliver 100,000ís of soldiers to the shores of Normandy at the start of the drive to Berlin. D-Day itself was on June 6th 1944.
The planning for D-Day began in 1943 at the Quebec Conference in Canada. The planned invasion was given the code-word "Overlord". It was believed by the Allies that the Germans expected an Allied attack at the nearest point to occupied Europe - the Pays de Calais. Their plan was for an attack on the beaches of Normandy, which would include a much longer crossing of the English Channel.
Why did the Allies decide to launch their invasion from Normandy? Intelligence reports suggested that the Normandy region was less well defended than the area around Calais. The length of the sea crossing made it an unlikely landing spot for the Allies - this is what the Allies hoped that the Germans would think.
Technical planning for D-Day had to start early. The beaches were secretly surveyed so that the Allies could find out about the sand/shingle on the beaches. The planned landing would require a large number of tanks and armoured vehicles to be landed along with infantry. What would happen if the sand or shingle was too fine to allow the movement of vehicles on the beaches? What would happen if the beaches got clogged up with vehicles that simply could not be moved? What if the beaches were too steep for military vehicles to operate effectively, leaving them open to German weapons?
The defences planned by Field Marshall Erwin Rommell were assessed. How difficult would these be to an Allied landing? Would these "dragon's teeth" stop landing craft from doing their job?
The French Resistance (the Marquis) had to be brought into the plan. They would end up doing a vital job on the night of D-Day and on the following days. But giving the Marquis too much information was dangerous as Allied planners could never be too sure if any part of the Marquis organisation had been compromised by traitors.
Normandy - or at least the area chosen for the invasion - had no natural harbour so the Allies had to plan to build an artificial harbour to take the hundreds of boats that would be used to supply the troops in the aftermath of the invasion - the legendary Mulberry Harbour.
Part of the Mulberry Harbour at Aromanche
All the military had to be supplied with fuel. A fuel line would be an obvious target for the German defenders - but not if it was under the water of the Channel. This lead to the making of PLUTO - Pipe Line Under The Ocean - an underwater fuel pipe line from England to Normandy.
This all had to be done before any consideration could be made for the actual landings!
The first day's assault targeted 5 beaches code-named Juno, Sword, Gold, Omaha and Utah. The Americans were to take Utah and Omaha beaches, the British were to take Gold and Sword beaches and the Canadians Juno beach. The plan was to land about 135,000 men on D-Day and about 20,000 vehicles. The invasion had been given a weather warning in that those in the military's Met Office considered a sea crossing too dangerous. D-Day had been delayed by 24 hours but in the early hours of June 6th 1944, Eisenhower gave the go-ahead for the invasion. The crossing was rough but with massive air superiority and with the protection of the Navy, those in the landing craft were relatively safe until the actual landing.
Bombers and fighter planes had softened up the sighted targets on the 5 beach heads; Allied paratroopers and the Marquis were creating chaos, as planned, in the immediate interior of Normandy and capturing vital targets such as bridges. Rail lines were destroyed to stop the Germans bringing in reinforcements.
Despite the enormous complexity of D-Day, it was a huge success. With the exception of the American landing at Omaha Beach - graphically portrayed in "Saving Private Ryan" - most of the landings were free from major casualties. The invasion had taken the Germans by surprise and the initiative lay with the Allies to advance through Normandy towards Paris.