NORMANDY CAMPAIGN BACKGOUND

D-Day, the invasion of Normandy on June 6, 1944, was the culmination of years in the planning stages and much discussion (to put it mildly) between the Allies. Dwight D. Eisenhower prepared the plan under the code name "Roundup". Later known as the Marshall Memorandum it called for an invasion of the European continent in 1942. George Marshall was so impressed with it that he presented it to President Roosevelt and Allied leaders. The plan called for a force of 48 divisions (30 U.S. and 18 British), of over 1.5 million men landing in France, between Boulogne and Le Havre, advancing on Antwerp. It was a very ambitious undertaking and required 7000 landing craft.
Another plan "Operation Slegehammer" called for 5 U.S. and British divisions to be landed in France if one of two criteria were met. The first event being the imminent collapse of Russia and the second being the critical weakening of Germany's military power. The Russians were urging the Allies to establish a "second front" to help take off the pressure the German's were putting on their military machine.
The British planned a raid on Dieppe in August of 1942 utilizing their Canadian forces, namely the 2nd Division. Essentially they were repulsed on the beach with heavy casualties during the morning hours. After this disaster even the most optimistic advocates of an invasion recognized it was premature, even 1943 might be too soon. It was Admiral Montbatten, architect of Dieppe, who showed it couldn't be done in 1942. The U.S. could only field three divisions in Britain, while the English had only thirteen divisions fit for action.
Together with the rather small number of troops, only 4000 could be landed with available landing craft. Another factor was air superiority. The Axis could respond with 1500 aircraft compared to the slightly lower number for the Allies. Since amphibious operations were extremely risky, air superiority is an absolute necessity in order to keep enemy planes from attacking ground and naval forces.
An invasion for 1943 was torpedoed by the British. Churchill felt that operations in the Mediterranean were
more appropriate for 1943. Despite the Operation Torch success which showed a large scale invasion on the continent was feasible, reasons were given to continue in the Mediterranean area. The U-boat problem in the North Atlantic were still a problem for convoys causing delays in troop and supply buildup in Britain. The Germans were on the defensive in Russia even though the Soviets were demanding a second front. The war in the Pacific had only 15% of the Allied strength and the military wanted more resources sent. Intelligence indicated that the Germans had 40 divisions in France against 22 the Allies could put against them. It was debated that knocking Italy out of the war would force the Germans to replace Italian troops in both Italy and the Balkan area now garrisoned by the Fascists. Turkey it was hoped would join the Allies after Italy's fall and provide bases from which to supply Russia.
The invasion of Sicily, Operation Husky, took place in July 1943, with 2500 ships and 100,000 men. Operation Overlord was planned for 1944 in conjunction with an invasion in southern France. It remained only to choose the Supreme Commander for the Expeditionary Force. Both General George C. Marshall and General Sir Alan Brooke were obvious choices but Roosevelt abandoned Churchill by picking Eisenhower. The President needed Marshall's advice at home. Eisenhower's subordinate would be General Bernard Montgomery.
Without hesitation Montgomery proposed changes in the plan. He convinced Ike to postpone the May date to June 5th. A month delay would provide another thousand landing craft to the 3000 already available and would accommodate 2 extra divisions, allowing for five landing sites rather than the three proposed. In addition the invasion area could be extended from 25 to 50 miles facilitating a combined Allied force landing side by side each deploying two and perhaps three corps. An airborne drop, division rather than brigade size, on the flanks was proposed to protect the flanks against counterattacks. Additionally, massive air bombardments were to disrupt rail and communications and establish air superiority by decimating the Luftwaffe. Furthermore, the navy was to provide extra warships for shore bombardment.
The invasion was put off one day because of bad weather. Weather reports from the Atlantic indicated it would be clearing up in time for a landing on June 6th. During the night of June 5-6th, over 5000 ships of a hundred different types launched from ports into the channel. The paratroopers in transports and gliders were on their way and would drop in the early morning hours. Over 6000 American and 5500 British planes would provide tactical support for the invasion fleet. 1200 warships of which 80 percent were British or Canadian would conduct the bombardment and security of the other 4000 ships. Of the 4200 U.S. built landing craft, 75 percent were crewed by Britains. Armies of six nations would be represented, the Americans, the British, the Canadians, the French, the Polish and the Germans.
The Germans had around 200 operational fighters, 30 fast E boats, 50 coastal U boats, a few destroyers and 23 heavy coastal batteries. Rommel had enhanced the Atlantic Wall fortification by sowing over 20 million mines on the beaches and possible glider landing sites. The Germans also thought they had high tides in their favor, convincing Field Marshall Rommel who was absent on that date. The German's were also convinced that the invasion would take place farther up the coast at Calais rather than Normandy which would be considered a diversion.
Once Eisenhower made the decision to invade, Montgomery took over as Commander of 21 Army Group. He controlled the American 1st Army under Bradley and the British 2nd Army under Dempsey. The invasion plan called for the landing of these two armies on five beaches from west to east namely -Utah and Omaha (US) and Gold (British), Juno (Canadian) and Sword (British). The westernmost beach (Utah) would be at the foot of the Cotentin peninsula, and the easternmost beach (Sword) would cover both sides of the Orne river running into the channel from the direction of the city of Caen, a first day objective.
As the hundreds of transport aircraft approached Francewith the three airborne divisions one of the more interesting diversionary operations took place. Three groups
of aircraft broke off from the main body and headed for Rouen, Caen, and Avranches. The bombers began dropping large amount of Window and then to simulate an airborne invasion dropped straw dummies out of the planes. German units rushed to the drop zones and much confusion reigned among the German commanders as they tried to piece together what was actually happening. Every additional hour that delayed
German reinforcements from attacking the vulnerable beachheads increased the chance of success. One of the regiments of the German 352nd Infantry Division was sent on a wild goose chase after these dummies; therefore it was not available to be on the beaches at Omaha. The presence of this unit could have caused Omaha Beach to be a total disaster.