Operation Fortitude

Operation Fortitude was the code name for a World War II military deception employed by the Allied nations as part of an overall deception strategy (code named Bodyguard) during the build-up to the 1944 Normandy landings. Fortitude was divided into two sub-plans, North and South, with the aim of misleading the German high command as to the location of the imminent invasion.

Both Fortitude plans involved the creation of fake field armies (based in Edinburgh and the south of England) which threatened Norway (Fortitude North) and Pas de Calais (Fortitude South). The operation was intended to divert Axis attention away from Normandy and, after the invasion on June 6, 1944, to delay reinforcement by convincing the Germans that the landings were purely a diversionary attack.

Background
Fortitude was one of the major elements of Operation Bodyguard, the overall Allied deception stratagem for the Normandy landings. Bodyguard's principal objective was to ensure the Germans would not increase troop presence in Normandy by promoting the appearance that the Allied forces would attack in other locations. After the invasion (on June 6, 1944) the plan was to delay movement of German reserves to the Normandy beachhead and prevent a potentially disastrous counter-attack. Fortitude's objectives were to promote alternative targets of Norway and Calais.

The planning of Operation Fortitude came under the auspices of the London Controlling Section, a secret body set up to manage Allied deception strategy during the war. However, the execution of each plan fell to the various theatre commanders, in the case of Fortitude this was Supreme Headquarters Allied Expeditionary Force (SHAEF) under General Dwight D. Eisenhower. A special section, Ops (B), was established at SHAEF to handle the operation (and all of the theatre's deception warfare). The LCS retained responsibility for what was called "Special Means"; the use of diplomatic channels and double-agents.

Fortitude was split into two parts, North and South, both with similar aims. Fortitude North was intended to convince the German high command that the Allies, staging out of Scotland, would attempt an invasion of occupied Norway. Fortitude South employed the same tactic, with the apparent objective being Pas de Calais.

Means
It was initially envisioned that deception would occur through five main channels:
 * 1) Physical deception: to mislead the enemy with nonexistent units through fake infrastructure and equipment, such as dummy landing craft, dummy airfields, and decoy lighting.
 * 2) Controlled leaks of information through diplomatic channels, which might be passed on via neutral countries to the Germans.
 * 3) Wireless traffic: To mislead the enemy, wireless traffic was created to simulate actual units
 * 4) Use of German agents controlled by the Allies through the Double Cross System to send false information to the German intelligence services
 * 5) Public presence of notable staff associated with phantom groups, such as FUSAG (First U.S. Army Group), most notably the well-known US general George S. Patton.

Contrary to popular belief, there was no use of inflatable tanks, or other decoy equipment as part of Fortitude, with the exception of dummy landing craft and dummy aircraft. The inflatable tanks, artillery, and trucks were only used on the continent as part of operational and tactical deceptions. It is thought that the Army encouraged the idea that these dummies were used to draw attention away from some of the other means of deception, such as turned agents.

During the course of Fortitude, the almost complete lack of German aerial reconnaissance, together with the absence of uncontrolled German agents in Britain, came to make physical deception almost irrelevant. The unreliability of the "diplomatic leaks" resulted in their discontinuance. The majority of deception was carried out by means of false wireless traffic and through German double agents. The latter proved to be by far the most significant.

In fact, Fortitude was so successful that Adolf Hitler regarded the Normandy invasion as a feint: he kept his Panzer units where he expected an attack and away from Normandy, until the battle was decided in Normandy.

Double agents
The Germans had about 50 agents in England at the time, but B1A (the Counter-Intelligence Division of MI5) had caught all but one of them (he died in unclear circumstances). Many were recruited as double agents under the Double Cross System. They were used throughout the war to feed German Intelligence a misleading picture and, particularly in the pre-invasion period, misleading information about invasion preparations. Reports sent by these agents were carefully composed and coordinated to support the view of forces in the UK the Allied deception planners wished to present.

The three most important double agents during the Fortitude operation were:
 * Joan Pujol Garcia (Garbo), a Spaniard who managed to get recruited by German intelligence, and sent them abundant but convincing misinformation from Lisbon, until the allies accepted his offer and he was employed by the British. He created a network of 27 imaginary sub-agents by the time of Fortitude, and the Germans unwittingly paid the British Exchequer large amounts of money regularly, thinking they were funding a network loyal to themselves. He was awarded both the Iron Cross by the Germans and an MBE by the British after D-Day.
 * Roman Czerniawski (Brutus), a Polish officer. Captured by the Germans, he was offered a chance to work for them as a spy. On his arrival in Britain, he immediately turned himself in to British intelligence.
 * Dusan Popov (Tricycle), a Yugoslav lawyer.

Fortitude North
Fortitude North was designed to mislead the Germans into expecting an invasion of Norway. By threatening any weakened Norwegian defence the Allies hoped to prevent or delay reinforcement of France following the Normandy invasion. The plan involved simulating a build up of forces in northern England and political contact with Sweden.

During a similar operation in 1943, Operation Cockade, a fictional field army (British Fourth Army) had been created, head-quartered in Edinburgh Castle. It was decided to continue to use the same force during Fortitude. Unlike its Southern counterpart the deception relied primarily on "Special Means" and fake radio traffic since it was judged unlikely that German reconnaissance planes could infiltrate Scotland without being stopped. False information about the arrival of troops in the area were reported by double agents Mutt and Jeff, who had surrendered following their 1941 landing in the Moray Firth, whilst the British media cooperated by broadcasting fake information, such as football scores or wedding announcements, to nonexistent troops. Fortitude North was so successful that by late spring 1944, Hitler had thirteen army divisions in Norway.

In the early spring of 1944 British commandos attacked targets in Norway to simulate the precursor to invasion. They destroyed industrial targets, such as shipping and power infrastructure, as well as military outposts. This coincided with an increase in Naval activity in the northern seas and political pressure on neutral Sweden.

Operation Skye
Operation Skye was the code name for the radio deception component of Fortitude North, involving simulated radio traffic between fictional army units. The programme began on 22 March 1944, overseen by Colonel R. M. McLeod, and became fully operational by 6 April). The operation was split into four sections, relating to different divisions of the Fourth Army:
 * Skye I; Fourth Army headquarters
 * Skye II; British II Corps
 * Skye III; American XV Corps (a genuine formation, but with fictional units added to its order of battle)
 * Skye IV; British VII Corps.

In his 2000 book, Fortitude: The D-Day Deception Campaign, Roger Hesketh concluded that "No evidence has so far been found to show that wireless deception or visual misdirection made any contribution to Fortitude North". It is thought that the Germans were not in fact monitoring the radio traffic being simulated.

Fortitude South
Fortitude South employed similar deception in the south of England, threatening an invasion at Pas de Calais by the fictional 1st U.S. Army Group (FUSAG). France was the crux of the Bodyguard plan; as the most logical choice for an invasion the Allied high command had to mislead the German defences in a very small geographical area. The Pas de Calais offered a number of advantages over the chosen invasion site, such as the shortest crossing of the English Channel and the quickest route into Germany. As a result German command, particularly Rommel, took steps to heavily fortify that area of coastline. It was decided, by the Allies, to amplify this belief of a Calais landing.

Montgomery, commanding the Allied landing forces, knew that the crucial aspect of any invasion was the ability to enlarge a beachhead into a full front. He also had only limited divisions at his command, 37 compared to around 60 German formations. Fortitude South's main aims were to give the impression of a much larger invasion force (the FUSAG) in the South-East of England, to achieve tactical surprise in the Normandy landings and, once the invasion had occurred, to mislead the Germans into thinking it a diversionary tactic with Calais the real objective.

Operation Quicksilver
The key element of Fortitude South was Operation Quicksilver. It entailed the creation of the belief in German minds that the Allied force consisted of two army groups, 21st Army Group under Montgomery (the genuine Normandy invasion force), and 1st U.S. Army Group (FUSAG) (a fictitious force under General George Patton), positioned in southeastern England for a crossing at the Pas de Calais.

At no point were the Germans fed false documents describing the invasion plans. Instead they were allowed to construct a misleading order of battle for the Allied forces. To mount a massive invasion of Europe from England, military planners had little choice but to stage units around the country with those that would land first nearest to the embarkation point. As a result of FUSAG's having been placed in the south-east, German intelligence would (and did) deduce that the center of the invasion force was opposite Calais, the point on the French coast closest to England and therefore a likely landing point.

To facilitate this deception, additional buildings were constructed; dummy vehicles and landing craft were placed around possible embarkation points. Furthermore, Patton was often photographed visiting these locations. It was originally intended to make many such fakes, but the extremely low level of German aerial reconnaissance and the belief that most German spies were under British control meant that such effort were reduced to a minimum. A huge amount of false radio traffic was transmitted, commensurate with a force of that size.

A deception of such a size required input from many organisations, including MI5, MI6, SHAEF via Ops B, and the armed services. Information from the various deception agencies was organized by and channeled through the London Controlling Section under the direction of Lieutenant-Colonel John Bevan.

Results
The Allies were able to judge how well Fortitude was working thanks to Ultra, signals intelligence obtained by breaking German codes and ciphers. On June 1, a decrypted transmission by Hiroshi Ōshima (the Japanese ambassador) to his government recounting a recent conversation with Hitler confirmed the effectiveness of Fortitude. When asked for his thoughts on the Allied battle plan, Hitler had said, "I think that diversionary actions will take place in a number of places - against Norway, Denmark, the southern part of western France, and the French Mediterranean coast". Adding that he expected the Allies to subsequently attack in force across the Straits of Dover.

They maintained the pretense of FUSAG and other forces threatening Pas de Calais for some considerable time after D-Day, possibly even as late as September 1944. This was vital to the success of the Allied plan, since it forced the Germans to keep most of their reserves bottled up waiting for an attack on Calais that never came, thereby allowing the Allies to maintain and build upon their marginal foothold in Normandy.

Reasons for success
Some of the key reasons why this operation was so successful:
 * The long term view taken by British Intelligence to cultivate these agents as channels of disinformation to the enemy.
 * The use of Ultra decrypts of machine-encrypted messages between Abwehr and the German High Command, which quickly indicated the effectiveness of deception tactics. This is one of the early uses of a closed-loop deception system. The messages were usually encrypted by Fish rather than Enigma machines.
 * R V Jones, the Assistant Director Intelligence (Science) at the British Air Ministry insisted for reasons of tactical deception that for every radar station attacked within the real invasion area, two were to be attacked outside it.
 * The extensive nature of the German Intelligence machinery, and the rivalry amongst the various elements.
 * General George S Patton was considered the Allies' best General and the German High Command believed he would lead the attack.

In fiction
Eye of the Needle is a novel (and subsequent movie) about a Nazi spy figuring out the Allied deception and racing to let the German leadership know. Another book, The Unlikely Spy, is a novel that focuses on Allied attempts to carry out Fortitude, as well as a German agent's race to discover the true plans. Blackout, as well as its sequel All Clear, is a novel about time-travelling historians who are studying the events of the Battle of Britain. One of the historians, posing as a contemporary British soldier, has been assigned to assist with Operation Fortitude.