Almost anyone with even a passing interest in the Second World War knows of Operation Overlord (D-Day) and its immense importance. Yet, far fewer have heard of another great military operation that helped to ensure Overlord’s success: Operation Fortitude. Here, Nathan Richardson explains what happened in the 1944 operation to fool the Nazis and make them think that the D-Day landings would take place in Calais, France and Norway – and not in their actual location of Normandy.
A dummy British RAF aircraft in October 1943. Source: The National Archives, available here.
In 1944, the combined British and American military chiefs, along with their various allies, were intently planning an invasion of Western Europe. They all knew Hitler’s “Fortress Europe” must be breached if the Western Allies were to bring the war effectively to Nazi Germany and take the pressure off of the beleaguered Russians. Fighting in Italy had taken a terrible toll on the Allied armies. Regrettably, Italy had not turned out to be the “weak underbelly” that Churchill had thought. Though the operations in Sicily and Italy had successfully forced the fascist Mussolini out of power and switched Italy over to the Allied side, German troops barred the Allies from crossing the Alps into Europe proper. The Allies decided that they must find another invasion route into Europe.
The Combined Chiefs of Staff, the Allied generals made up of both British and American commanders and headed by General Eisenhower, determined that an amphibious assault must be made from Britain into Western Europe. Where and when were the only remaining questions. Ultimately, Normandy, France and June were the location and time decided upon. Yet, keeping this information from the Germans could very well decide the success or failure of the invasion. Churchill, though convinced of the necessity of an invasion, nevertheless greatly feared its results if it turned out to be a disaster, which it very well could have been (Keegan 164-5).
However, Eisenhower, who held the gut-wrenching last word on when the invasion took place, went to impressive lengths to keep the Germans as much in the dark as possible. That an invasion was coming, the Germans knew for a fact—it was inevitable that the Allies would attempt to retake Occupied Europe. Indeed, Hitler had been making enormous preparations on his coastal defenses, stretching from Norway in the north, down the whole coast, all the way down the English Channel. However, this impressive length of coastline defenses was never completed, and never lived up to its propaganda—nor did it live up to the faith that Hitler placed in it (Esposito 66). Naturally, the Germans knew they must decide which areas were most likely to be assaulted, and to build their best defenses there. Deciding that the Allies must need a port to sustain an invasion, the Germans centered their heaviest weapons and fortifications at port-cities such as Cherbourg, Calais, and Antwerp (Weinberg 685).
Not illogically, the German High Command decided that the most likely invasion point was the Pas de Calais, with its port close at hand, and it being the closest point between Europe and England. Why would the Allies travel farther than necessary? Would not the Allies enjoy greater air cover from their powerful air forces the closer they were to England? Thus, the Germans centered the bulk of their divisions in the West around Calais, and there put their best forces, ready to repel at this likely invasion site (Ambrose, Ike’s Spies 88). However, this was exactly why the Allies knew they must not attack where the Germans expected them. Eisenhower knew he must keep the Germans from knowing the true invasion point. In order to do that, he made sure the Germans found evidence that seemed to confirm their preconceived ideas. The Germans must be convinced that Calais was the true planned site of the invasion, and that any other attack was just a diversion (Ambrose, Ike’s Spies 82, 88). To accomplish this trickery, the Allies employed some truly ingenious schemes.
German Spies Flipped
World War Two was a war of spies and espionage. In an age of rapidly advancing weaponry and innovative tactics, spies were absolutely essential in keeping the commanders on both sides knowledgeable of the enemy’s capabilities and plans. Yet, the Allies were able to effectively deprive the Germans of their ability for espionage, and turn any German spies into Allied agents, who would turn around and feed the Germans false information about the Allies. How was this done? The British Secret Service identified German spies and carefully evaluated them. If German spies were deemed suitable (i.e., most likely to cooperate with the Allies), they were convinced to turn ‘double-agent’, and to report to the Abwehr (the German military intelligence) exactly what the British wanted them to know. Those spies who were not deemed suitable or who did not cooperate were either executed or imprisoned. This system was known as the Double-Cross System. Thus, not only did the Allies control the German spies, but with the ability to intercept German coded radio transmissions due to British code breaking (known as ULTRA), the Allies could confirm that the Germans were receiving the information the Allies wanted them to receive, and could also confirm whether the Germans believed what they were being told (Ambrose, Ike’s Spies 77). This system of turning German spies into double-agents had carefully been built up since the beginning of the war. Yet, British intelligence knew that using the Double-Cross System to the Allies’ advantage could likely only be used once, since the Germans would eventually realize they had been duped, and the Allies would never have such an opportunity again. So, the British were forced to sit by and patiently wait to use this weapon until the perfect time. That time was D-Day. Until then, the British carefully fed the Germans true and valuable information to ensure the Germans trusted and valued their agents, while also taking care not to feed them information that would be militarily damaging (Ambrose, Ike’s Spies 78).
Operation Fortitude
The last thing the Allies wanted was for the Germans to realize that their spies had become compromised. The Germans must see tangible evidence that what their spies were reporting was true. Enter: Operation Fortitude. Operation Fortitude was designed to fool the Germans into believing that the Allies were attacking at Calais, France and southern Norway, which would hopefully cause the Germans to concentrate their best defensive efforts at these points - and away from Normandy (Ambrose, Ike’s Spies 82).
A seaborne invasion, of course, necessitates a massive buildup of men and materials. Shipping of all sorts must be concentrated at the embarkation points. Supplies of every sort, including a massive number of vehicles, such as tanks, trucks, and jeeps. Fighter and bomber aircraft, ready to provide air support for the attackers, must be kept in readiness at airfields close to the invasion beaches. For a Normandy landing, this massive buildup must be assembled in and around ports in the south of England, at important port cities such as Plymouth, Dartmouth, Portland, and multiple others (Esposito 67). How could these preparations be kept hidden? They could not fully keep them hidden, despite the Allies’ best efforts. No amount of care and camouflage could keep German scouting planes from picking up the U.S. 4th Infantry division near Plymouth or the British 50th Armored Division west of Poole or the Canadian 3rd Infantry division near Portsmouth (Esposito 67). The location of these troops, if spotted, would show the Germans that Normandy was a more likely invasion site. Contrarily, the empty fields and ports of southeast England around Dover (the closest point between England and France), would indicate that Calais was not the target. Despite all of the Allied efforts to hide and disguise their readying of forces and to muzzle or flip the German spies, the Germans might still catch on, and the result might lead the Allies to an enormous defeat.
Thus, the only way to keep the Germans from guessing the true invasion point, was to provide a distraction. This distraction was Operation Fortitude. Operation Fortitude was a dummy Operation, involving dummy formations of troops. In Scotland, the completely fake British “Fourth Army” was stationed, ready to assault southern Norway. In the southeast of England, the bogus First United States Army Group (FUSAG) was stationed, across from Calais, right where the Germans expected to see such an Army Group stationed (Ambrose, Ike’s Spies 82). To make FUSAG look like a real army group to the Germans (from far enough away at least), the Allies built poorly camouflaged dummy landing craft and fields of papier-mâché tanks. To make the tanks look more legitimate, jeeps were used to drag chains around the tanks to create “tank tracks” and to kick up dust, indicating movement. Hitler’s spies obediently reported all of these fraudulences as the real thing (Ambrose, Ike’s Spies 84). Fake radio traffic was also broadcast around the assembly areas for these fake armies. The British Fourth Army, which was entirely fictional (FUSAG was made up of some real units, though not all were even in England yet), knew that the Germans, due to their expertise in intercepting and decoding their enemy’s radio transmissions, were able to geographically pinpoint the location of the Fourth Army headquarters (which was Edinburgh Castle), as well as locating and identifying divisional and corps command posts (Ambrose, Ike’s Spies 82-3, 85). The Allies would use the Germans’ proficiency against them with great effect.
The already-famous General George S. Patton was placed in command of this force, giving further credence to the Army Group he supposedly led, since the Germans believed him the best Allied general. In reality, Eisenhower considered Patton more in his element when the time came for an impetuous drive across France, so Patton was given this unconventional role and saved for later (Ambrose, Ike’s Spies 85). With control over the German spies in Britain, the Allies could control in large part what information the Germans received, and what they did not receive. Also, with the ability to read the German codes, the Allies could see the Germans’ react to the false reports, and could tell whether the Germans were buying it or not. Even if some information indicating Normandy as the main landing area came into German hands, this information would be buried amidst a far greater volume of reports that said the Allies were getting ready to attack Calais (Weinberg, 682).
Dummy landing craft used as decoys in south-eastern England harbours in the period before D-Day, 1944.
The German Defenses Affected by Fortitude
Operation Fortitude worked so successfully that the Germans believed not only that the Pas de Calais was the main target (which Hitler and General von Rundstedt, the commander in the West, both agreed would be the case), but that the Allies actually had far greater capabilities than they actually possessed (Ambrose, Ike’s Spies 84, 87). From the intercepted and decoded German radio messages, the Allies could tell that the Germans figured Eisenhower had twice as many forces as he actually had (the Germans counted eighty-nine Allied divisions, rather than the forty-seven Ike actually had), and that he had four times as many landing craft, which were actually in very short supply (Ambrose, Ike’s Spies 87, 83). Believing that Eisenhower had so many men and landing craft at his disposal, the Germans easily believed that Ike had enough power for diversionary assaults in addition to the main assault—which, in the end, kept the Germans from reacting swiftly and with enough force against the Normandy assault. In fact, the lie that Normandy was just a diversion for a Calais assault lasted until nearly two months after the Allied invasion, well after the beachhead had been secured and the push inland accomplished (Ambrose, Ike’s Spies 100; Esposito 83). Fifteen German divisions, the bulk of the Fifteenth Army, which were the best-equipped the Germans had in France, were kept out of the fight in Normandy altogether, awaiting another threat that never came (Ambrose, Ike’s Spies 88, 100). The distraction caused by the bogus British Fourth Army was no less successful. Hitler was so convinced that an attack was coming that he reinforced the Norwegian garrisons, leaving them with thirteen divisions—twice as many troops as were needed for the occupation. An additional 90,000 naval and 60,000 air personnel were also left to guard Norway, along with an armored division—all of which would have served a far better purpose in Normandy (Ambrose, Ike’s Spies 84).
Conclusion
In summary, Operation Fortitude, which masterfully employed the resources that the Double-Cross System provided, managed to utterly fool the Germans into believing that the main attack was coming anywhere but Normandy. It can even be said that if Operation Fortitude had not succeeded, Operation Overlord would have failed. The Allies simply did not have the means to transport enough men to France quickly enough to meet the full force of the German occupation troops in the West if Fortitude failed to hold them back (Ambrose, Ike’s Spies 88-9). Eisenhower wrote frankly in February of 1944, just months before the great invasion, that “The success or failure of coming operations depends upon whether the enemy can obtain advance information of an accurate nature” (Ambrose, D-Day 83). The success of the Normandy invasion was just the first step in the freeing of all Europe from the terror of Nazi occupation. Thus, Operation Fortitude did incalculable service in the Allied effort to rid the world of Nazism.
What do you think the significance of Operation Fortitude was? Let us know below.
References
Ambrose, Stephen Edward. D-Day, June 6, 1944: The Climactic Battle of World War II. Simon & Schuster, 1994.
Ambrose, Stephen Edward. Ike’s Spies: Eisenhower and the Espionage Establishment. Doubleday, 1981.
Esposito, Vincent J. The West Point Atlas of War. European Theater. Tess Press, 1995.
Keegan, John. Winston Churchill. Viking Penguin, 2002.
Weinberg, Gerhard. A World at Arms: A Global History of World War II. 2nd ed., Cambridge University Press, 1994.
