Operation OVERLORD, the invasion of Normandy, France, on 6 June 1944, was the Western Allies' greatest operation of World War II and the finest hour of Anglo-American cooperation. Only the United States and the British Empire could have successfully undertaken the largest and most dangerous amphibious assault in history. The operation was so complicated that U.S. Army Chief of Staff General George C. Marshall said it "almost defies description." The Allies assembled 2 million troops of numerous nationalities, nearly 5,000 ships, and 11,000 aircraft without the Germans knowing where or when the invasion would take place.
British Prime Minister Winston L. S. Churchill, already thinking offensively shortly after the evacuation of the British Expeditionary Force from Dunkerque in May-June 1940, established the Office of Combined Operations to plan raids on Nazi-occupied Europe. A cross-Channel invasion became likely after the December 1941-January 1942 ARCADIA Conference in Washington, which reaffirmed British-U.S. determination to defeat Germany first. General Marshall flew to Britain in April to propose an early opening of the second front (code-named SLEDGEHAMMER), and although he returned to Washington in the belief that an invasion of the Continent would take place within a year, the British sent Vice Admiral Lord Louis Mountbatten, head of Combined Operations, to Washington in June to tell the Americans that a cross-Channel invasion was not possible in 1942. This was confirmed in the disastrous Allied Dieppe raid of 19 August 1942.
At the January 1943 Casablanca Conference, where U.S. President Franklin D. Roosevelt and Churchill agreed to exploit Allied success in North Africa, they also stipulated that preparations for a cross-Channel attack should continue. Shortly after Casablanca, General Frederick E. Morgan was appointed chief of staff to the Supreme Allied Commander (designated COSSAC), and a small Anglo-American planning group began work in Norfolk House, St. James's Square, London, on what would become the greatest military operation in history. Its objective was to mount an invasion with a target date of 1 May 1944 "to secure a lodgment on the Continent from which further offensive operations can be carried out."
By the end of July 1943, the Anglo-American COSSAC staff had produced a 113-page plan for OVERLORD. Limited by a lack of amphibious landing craft, the initial plan called for a three-division assault along a 30-mile front. After a weekend conference at Largs in Scotland, planners selected the Normandy coast as offering the best chance for success. An invasion there would be most likely to surprise the Germans, who would expect the invasion to occur in the closed point to Britain, the Pas de Calais, and who concentrated their defenses on that stretch of the French coast. Normandy was within the maximum range of Allied air cover. The Allies hoped that it would result in early capture of the port of Cherbourg. The disastrous failure of the Dieppe raid, in which the attacking Canadians suffered 60 percent casualties, appeared to rule out a direct attempt to seize a major port. The Allied answer was to build, to tow across the Channel, and to assemble their own artificial harbors, known as Mulberries.
COSSAC planners examined meticulously the requirements necessary for successful invasion. These included such variables as weather, tide and moon conditions, and sand on the landing-site beaches. All were designed to produce a solution to the ultimate question of where and how a cross-Channel invasion could be launched.
An essential part of planning for OVERLORD included an elaborate deception plan, the largest of the war by either side. Originally the brainchild of COSSAC staff, the operation, code-named FORTITUDE, involved a massive effort to deceive Germany about the date and place of the invasion. It saw the "creation" of a nonexistent U.S. army to mislead the Germans into believing that the Normandy landings were merely a feint and that the main landing would be under the command of Lieutenant General George S. Patton in the Pas de Calais. The ruse reinforced the already existing German conviction that the main landing would indeed take place in that part of France closest to Britain. Another part of FORTITUDE was to draw off resources from France by convincing the Germans that the Allies also intended to invade Norway. Both aspects of FORTITUDE worked to perfection.
On 6 December 1943, Roosevelt named General Dwight D. Eisenhower as Commander of Supreme Headquarters, Allied Expeditionary Forces (SHAEF), which replaced COSSAC. Morgan continued on as deputy chief of staff, SHAEF. Both Eisenhower and British General Bernard L. Montgomery, who was designated ground forces commander for D day, argued for a month's delay of the invasion until June in order to obtain another month's production of the critically important landing craft. Acquisition of these was necessary to increase from three to five the number of divisions in the initial assault. The delay would also allow increasing the number of airborne divisions to protect the flanks of the 50-mile beachhead from two to three. Churchill opined that the invasion "seemed to be tied up in some god-damned things called LSTs [landing ship tank]."
The scale of preparations for OVERLORD was staggering. In the four months before D day, plans poured forth from SHAEF and Allied armies. The First U.S. Army, in association with the Western Naval Task Force and the Ninth Tactical Air Force, planned the landings on Omaha and Utah Beaches. The Second British Army, in association with the Eastern Naval Task Force and the British Second Tactical Air Force, planned the landings on Sword, Juno, and Gold Beaches. The Ninth Air Force's plan for the invasion alone ran 847,500 words in 1,376 pages and weighed more than 10 pounds.
By June 1944, there were 1,536,965 U.S. troops in Britain. Stockpiles of equipment for the invasion came to 2.5 tons and included everything from artillery and bulldozers to dental chairs and tanks. Wags remarked that only the barrage balloons overhead kept the British Isles from sinking under the weight of men and equipment. Administrators required each unit landing in France to carry a 30-day supply of blank forms and stationery. Approximately 7 million tons of oil were stored in the United Kingdom.
On the eve of D day, 2,700 vessels (not counting the 1,897 smaller landing craft carried in the landing ships) were steaming toward Normandy. No fewer than 195,000 sailors manned the invasion fleet, carrying 130,000 troops, 12,000 vehicles, 2,000 tanks, and nearly 10,000 tons of stores. Overhead, thousands of Allied fighters provided a protective umbrella for the invasion force.
Fortunately, OVERLORD planners had the invasions of North Africa, Sicily, and Italy, as well as amphibious operations in the Pacific, as guides for their D day planning. Allied planning for OVERLORD, based on honest debate, cooperation, and teamwork, laid the groundwork for the massive defeat of the German army in the Battle of Normandy.
Colin F. Baxter
Baxter, Colin F. The Normandy Campaign, 1944: A Selected Bibliography
. New York: Greenwood Press, 1992.
D'Este, Carlo. Eisenhower: A Soldier's Life
. New York: Henry Holt, 2002.
Harrison, Gordon. A United States Army in World War II: The European Theater of Operations: Cross-Channel Attack
. Washington, DC: Government Printing Office, 1951.
Morgan, General Sir Frederick E. Overture to OVERLORD
. New York: Doubleday, 1950.
Normandy, Invasion of
The cross-Channel invasion of France. U.S. officials, principally army chief of staff General George C. Marshall, had long sought the earliest possible invasion of France as the way to win the war in the shortest possible time. They supported both GYMNAST, a British cross-Channel invasion contingency plan for late 1942, and ROUNDUP, a 48-division invasion of France projected to occur by April 1943. The failure of the Allied raid on Dieppe, France (Operation JUBILEE), on 19 August 1942, however, led the Americans to concede to the British position that a cross-Channel invasion was many months, if not years, in the future. Prime Minister Winston L. S. Churchill and British planners, meanwhile, sought to interest the United States in a more opportunistic approach that would include operations in the Mediterranean Theater, and the Americans reluctantly went along.
This led to Operation TORCH, the Allied invasion of North Africa, and to subsequent British and U.S. landings in Sicily and Italy. The United States insisted, however, that the Italy Campaign would be a limited effort. At the Tehran Conference in November 1943, Soviet leader Josef Stalin had pressed President Franklin D. Roosevelt and Churchill for the cross-Channel invasion. Stalin agreed to mount a major offensive by the Soviets on the Eastern Front to coincide with the landing. He also pressed Roosevelt to name the commander of the invasion force, and shortly after the conference Roosevelt appointed General Dwight D. Eisenhower to the post of Supreme Commander, Allied Expeditionary Forces.
Fortress Europe and its coasts of Holland, Belgium, and France bristled with all manner of German fortifications and booby traps. Organization Todt had begun erecting defenses there in mid-1942. Over the next two years, the Germans used some 17.3 million cubic yards of concrete and 1.2 million tons of steel in thousands of fortifications. Field Marshal Erwin Rommel, who had command of Army Group B and the coastal defenses, disagreed with German commander in chief West Field Marshal Gerd von Rundstedt. Rommel, well aware from the campaign in North Africa what complete Allied domination of the air would mean, believed that, if it was to be stopped at all, the invasion had to be defeated on the beaches. Rommel told Adolf Hitler, "If we don't manage to throw them back at once, the invasion will succeed in spite of the Atlantic Wall." Rundstedt and Hitler placed their hopes in a large mobile reserve that would defeat the Allied forces once they were ashore. Indeed, Hitler seems to have welcomed the invasion as a chance to engage and destroy the British and U.S. forces. In Britain, the Allied armies could not be touched; in France, they could be destroyed. Hitler was convinced that the Allied effort would result in another Dieppe. "Let them come," he said. "They will get the thrashing of their lives."
Rommel did what he could, supervising the construction of elaborate defenses, the placement of a half million foreshore obstacles, and the laying of some 4 million mines. Rommel had at his disposal in the Fifteenth Army in northern France and the Seventh Army in Normandy a total of 25 static coastal divisions, 16 infantry and parachute divisions, 20 armored and mechanized divisions, and 7 reserve divisions. The Germans were weak in the air and on the water, however. The Third Air Fleet in France deployed only 329 aircraft on D day, whereas German naval forces in the area consisted of 4 destroyers and 39 E-Boats. Germany also deployed several dozen U-boats, most from French ports, during the campaign.
Meanwhile, U.S. and British aircraft worked to soften the German defenses and isolate the beachheads. Between 1 April and 5 June 1944, Allied aircraft flew 200,000 sorties in support of the coming invasion and dropped 195,000 tons of bombs. The Allies lost 2,000 of their own aircraft in the process, but by D day they had largely isolated the landing areas, and they had achieved virtually total air supremacy.
The Germans also greatly strengthened the Channel port defenses, which Hitler ordered turned into fortresses. All of this was for nought because, as German Minister of Armaments Albert Speer noted, the Allies came over the beaches and "brought their own port with them. ... Our whole plan of defense had proved irrelevant." In one of the greatest military engineering achievements in history, thousands of men labored in Britain for months to build two large artificial harbors known as "Mulberries." Plans called for these, after the initial Allied landings, to be hauled across the Channel from Britain and sunk in place. Their importance to the Allied cause may be seen in that, by the end of October, 25 percent of stores, 20 percent of personnel, and 15 percent of vehicles had passed through Mulberry B.
The Allies worked out precise and elaborate plans for the mammoth cross-Channel invasion, code-named OVERLORD, to occur on the Cotentin Peninsula in Normandy. British Admiral Bertram H. Ramsay had overall command of the naval operation, code-named NEPTUNE, and British General Bernard Montgomery exercised overall command of the land forces. The object of the operation was "to secure a lodgement on the continent, from which further offensive operations can be developed."
The landing itself would be preceded by a night drop of paratroops. General Marshall, an enthusiastic supporter of airborne forces, urged the use of five airborne divisions, but Eisenhower had his doubts, and as it transpired, only three were used: the British 6th and the U.S. 82nd and 101st. The lightly armed paratroopers, operating in conjunction with the French Resistance, had the vital task of securing the flanks of the lodgment and destroying key transportation choke points to prevent the Germans from reinforcing their beach defenses. The German 21st Panzer and 12th Schutzstaffel (SS) Panzer divisions were stationed just outside Caen. If they were permitted to reach the beaches, they could strike the amphibious forces from the flank and roll them up.
The amphibious assault would occur early in the morning after the airborne assault with 5 infantry divisions wading ashore along the 50-mile stretch of coast, divided into 5 sectors. The designated beaches were, from west to east, the U.S. 4th Infantry Division (Utah), the U.S. 1st Infantry (Omaha), the British 50th Infantry (Gold), the Canadian 3rd Infantry (Juno), and the British 3rd Infantry (Sword). Operation OVERLORD proved a vast undertaking. The airborne forces alone would require 1,340 C-47 transports and 2,500 gliders. Ten thousand aircraft would secure the skies. Naval support for the invasion would come from 138 bombardment warships, 221 destroyers and other convoy escorts, 287 minesweepers, 495 light craft, and 441 auxiliaries. In addition, there were 4,000 landing ships and other craft of various sizes.
Invasion commander General Eisenhower faced a difficult decision, given terrible weather in the days preceding the planned landing. Informed by his chief meteorologist that a break in the weather might occur, Eisenhower decided to proceed. This decision worked to the Allies' advantage, for the Germans did not expect a landing in such poor weather. The French Resistance was informed by radio code, and the airborne forces took off.
The airborne operation involving 23,400 U.S. and British paratroops occurred on schedule on the night of 5-6 June, but thick cloud banks over Normandy caused pilots to veer off course to avoid midair collisions. German antiaircraft fire, jumpy flight crews, and Pathfinders who were immediately engaged in firefights on the ground and unable to set up their beacons led to premature drops and to paratroopers being scattered all over the peninsula. Some were even dropped into the English Channel, where they were dragged down by their heavy equipment. Gliders crashed into obstacles, and they and the paratroopers came down in fields that had been deliberately flooded by the Germans as a defensive measure. Much equipment was thus lost. Nonetheless, the wide scattering of forces caused confusion among the defenders as to the precise Allied plans. Officers collected as many men as they could, and improvised units were soon moving on the objectives, most of which were secured.
Success was likely if the Allies could establish a bridgehead large enough to allow them to build up their strength and overcome the German defenders. Once they broke out, the Allies would have the whole of France for maneuver, because their armies were fully mechanized and the bulk of the defending German forces were not. The only possibility of German success was for the defenders rapidly to introduce panzer reserves, but this step was fatally delayed by two factors. The first was Allied naval gunfire support and air superiority of 30:1 over Normandy itself (there were large numbers of ground-support aircraft, especially the P-47 Thunderbolt and the P-51 Mustang). The second factor was Hitler's failure immediately to commit resources available elsewhere. Hitler was convinced that the invasion at Normandy was merely a feint and that the main thrust would come in the Pas de Calais sector. Allied intelligence played a key role in deluding him.
The British "doublecross" system worked to perfection. Every German agent in Britain was either dead, jailed, or working for British intelligence. The British actually controlled the entire German spy network in the United Kingdom and used it to feed disinformation to the Germans. Operations FORTITUDE NORTH and FORTITUDE SOUTH also deceived Hitler. Operation FORTITUDE NORTH caused him to believe that the Allies intended to invade Norway from Scotland, leading him to maintain and even reinforce substantial German units there; FORTITUDE SOUTH led Hitler to believe that the main Allied effort in France would come in the form of a subsequent landing in the Pas de Calais area, the narrowest point of the English Channel, and that the lodgment in Normandy was only a feint. To this end the Allies created the "First U.S. Army Group" under Lieutenant General George S. Patton, still without command following an incident in which he had slapped soldiers suffering from combat fatigue in Sicily. The Germans expected the aggressive Patton would command any Allied invasion of the Continent. First U.S. Army Group, a notional formation of 18 divisions and 4 corps headquarters, contributed nothing to OVERLORD but did confuse the Germans.
Not until late July did Hitler authorize the movement of the Fifteenth Panzer Army from the Pas de Calais to Normandy. In effect, the deception totally immobilized 19 German divisions east of the Seine. Although units of the Fifteenth Army were moved west to Normandy before that date, this was done piecemeal and hence they were much easier for the Allies to defeat.
Meanwhile, the Normandy invasion began. In the days before the invasion, some 2,700 vessels manned by 195,000 men were on the move. They transported 130,000 troops, 2,000 tanks, 12,000 other vehicles, and 10,000 tons of supplies. At about 5:30 A.M. on June 6, 1944, the bombardment ships opened up against the 50-mi-long invasion front, engaging the German shore batteries. The first U.S. assault troops landed 30 to 40 minutes later, and the British landing craft were ashore 2 hours later.
The landing was in jeopardy only on Omaha Beach, where, because of rough seas, only 5 of 32 amphibious duplex-drive tanks reached the shore. Support artillery was also lost when DUKW amphibious trucks were swamped by the waves. Some landing craft were hit and destroyed, and those troops of the 1st Infantry Division who gained the beach were soon pinned down by a withering German fire. U.S. First Army commander Lieutenant General Omar N. Bradley even considered withdrawal. At 9:50 A.M., the gunfire support ships opened up against the German shore batteries. Destroyers repeatedly risked running aground to provide close-in gunnery to assist the troops ashore; indeed several destroyers actually scraped bottom. It was nearly noon before the German defenders began to give way. The 1st Infantry Division overcame German opposition with sheer determination reinforced by the knowledge that there was no place to retreat.
The landings on the other beaches were much easier. Overall, for the first day, the Allies sustained some 10,300 casualties - 4,300 British and Canadian and 6,000 U.S. A recent study suggests that a nighttime landing would have produced fewer casualties. The Allies had used nighttime landings with great success in the Mediterranean, but Montgomery believed that overwhelming Allied air and naval power would make a daytime landing preferable. Still, the losses were comparatively light.
Spencer C. Tucker
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. New York: Overlook Press, 2000.
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. Chapel Hill: University of North Carolina Press, 2001.
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