Since their colonization in the 15th century the Azores islands became a bastion of Portuguese power protecting lines of communications to its overseas empire. The advent of flight increased the strategic importance of the Azores. During World War I, it allowed the US to establish naval bases in Horta and Ponta Delgada and in 1918.
At the outbreak of the Second World War Salazar’s dislike of the Nazi regime in Germany and its imperial ambitions was tempered only by his view of the German Reich as a bastion against the spread of communism. He had favoured the Spanish nationalist cause, fearing a communist invasion of Portugal, yet he was uneasy at the prospect of a Spanish government bolstered by strong ties with the Axis. Salazar's policy of neutrality for Portugal in World War II thus included a strategic component. The country still held overseas territories that, because of their poor economic development, could not adequately defend themselves from military attack. Upon the start of World War II in 1939, the Portuguese Government announced, on 1 September, that the 600-year-old Anglo-Portuguese Alliance remained intact, but that since the British did not seek Portuguese assistance, Portugal was free to remain neutral in the war and would do so.
During 1940–41 the US, Britain and Germany each made plans to occupy the islands. Despite the fact that the islands were only 720 miles from Lisbon and 2100 from New York, in 1940 Roosevelt considered including both the Azores and Cape Verde Islands under the Monroe Doctrine of 1825. Roosevelt declared that German occupation of the Azores or the Cape Verde Islands would compromise US safety and on 22 May 1941 he directed the U.S. Army and Navy to draft an official plan, War Plan Gray, to occupy the Portuguese Azores.
In 1941, Portuguese officials recognizing the possible dangers of the Azores in German hands, expanded the runway and sent additional troops and equipment to Lajes including Gladiator aircraft. The Portuguese declared the base capable of air defence on 11 July 1941.
In December 1941, in a pre-emptive strike, Dutch and Australian troops invaded Portuguese Timor and Portugal immediately protested at the violation of her neutrality. Troops were dispatched from mainland Portugal but were still in the middle of the Indian Ocean when the Japanese invaded Portuguese Timor in January 1942. Salazar's protests concerning the violation of his country's sovereignty and neutrality by the Allies and subsequent Japanese invasion of Portuguese territory, would become a strong argument for Portugal not wanting to concede further facilities to the allied cause.
By 1943 American military strength had significantly increased and successes in North Africa Campaign had greatly reduced the chances of a German occupation of Iberia in retaliation against an allied seizure of the Azores. In May, in the Third Washington Conference, codenamed Trident, the conference members agreed that the occupation of the Azores was essential to the conduct of the anti-U-boat campaign, extending Allied air cover for convoys and increasing harassing activities against U-boats. In August 1943 the British requested military base facilities in the Azores, invoking the Anglo-Portuguese Alliance, Salazar responded favourably and quickly: Portugal allowed these bases, letting the British use the Azorean ports of Horta and Ponta Delgada, and the airfields of Lajes Field and Santana Field.
Operation Berlin was a successful commerce raid performed by the German battleships Scharnhorst and Gneisenau between January and March 1941. The commander-in-chief of the operation was Admiral Günther Lütjens, who subsequently commanded the famous cruise of Bismarck and Prinz Eugen.
The two ships aborted the operation in December 1940, but finally sailed from Kiel on 22 January 1941. They were spotted en route through the Great Belt and the British Admiralty was informed. Admiral Sir John Tovey sailed with a strong force (three battleships, eight cruisers and 11 destroyers), hoping to intercept the German ships in the Iceland—Faroe Islands Passage. Instead, Lütjens took his flotilla through the Denmark Strait into the Atlantic, where they were positioned to intercept convoys between Canada and Britain.
Convoy HX 106 was intercepted, but the attack was aborted when the escorting battleship HMS Ramillies was spotted. Lütjens had orders to avoid action with enemy capital ships. The British failed to make an accurate identification of the German battleships.
After refuelling, the German ships missed convoy HX 111, but happened upon an empty convoy returning to the U.S. Over 12 hours, five ships were sunk but the attack was reported. The squadron moved south to the Azores to intercept the convoy route between West Africa and Britain.
A convoy was sighted but, once again, was not attacked due to the presence of the battleship HMS Malaya. Instead, Scharnhorst and Gneisenau shadowed it, acting to guide in U-boat attacks. The two ships moved back to the western Atlantic, sinking a solitary freighter en route. Two unescorted convoys were attacked and 16 ships were sunk or captured. One of these ships—Chilean Reefer—caused problems. It made smoke, radioed an accurate position and returned Gneisenau's fire with its small deck gun. Lütjens, uncertain of the freighter's capabilities, withdrew and destroyed it from a safe distance. During this action, HMS Rodney appeared, possibly in response to the radio calls. The German ships bluffed their way to safety while Rodney picked up survivors.
The German ships were ordered back to Brest. They met air and sea escorts on 21 March and docked the next day.
Fortitude was one of the major elements of Operation Bodyguard, the overall Allied deception strategy 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 the 6th June 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.
Fortitude was split into two parts, 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.
The first version of the Fortitude South plan was produced in early January 1943 and aimed to counter the likelihood that the Germans would notice invasion preparations in the South of England. The intention was to create the impression that an invasion was aimed at the Pas de Calais sometime in mid-July; once the real invasion had landed, six fictional divisions would keep this threat to Calais alive. The Fortitude South plan would be implemented, at an operational level, by the invasion force—the 21st Army Group under the command of General Bernard Montgomery.
For deceptions, the Allies had developed a number of methodologies, referred to as "special means". They included combinations of physical deception, fake wireless activity, leaks through diplomatic channels, and double agents. Fortitude used all of these techniques to various extents. For example, Fortitude North relied heavily on wireless transmission (the Allies thought that Scotland was too far for German reconnaissance to reach) while Fortitude South utilised the Allies network of double agents.
Physical deception: to mislead the enemy with non-existent units through fake infrastructure and equipment, such as dummy landing craft, dummy airfields, and decoy lighting.
Controlled leaks of information through diplomatic channels, which might be passed on via neutral countries to the Germans.
Wireless traffic: To mislead the enemy, wireless traffic was created to simulate actual units.
Use of German agents controlled by the Allies through the Double Cross System to send false information to the German intelligence services.
Public presence of notable staff associated with phantom groups such as FUSAG, most notably the well-known US general George S. Patton.
One of the main deception channels for the Allies was the use of double agents. B1A (the Counter-Intelligence Division of MI5) had done a good job intercepting all of the German agents in Britain. Many of these were recruited as double agents under the Double Cross System. The three most important double agents during the Fortitude operation were:
Juan Pujol García (Garbo), a Spanish citizen who managed to get recruited by German intelligence, and sent them abundant but convincing disinformation 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 who ran an intelligence network for the Allies in occupied France. Captured by the Germans, he was offered a chance to work for them as a spy. On his arrival in Britain, he turned himself in to British intelligence.
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, headquartered 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 reach Scotland un-intercepted. False information about the arrival of troops in the area was reported by double agents Mutt and Jeff, who had surrendered following their 1941 landing in the Moray Firth, while the British media cooperated by broadcasting fake information, such as football scores or wedding announcements, to non-existent 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 preparations for 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.
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. The Allies decided 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.
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 deduce that the centre 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 aircraft and landing craft were placed around possible embarkation points. Patton paid many of these a visit along with a photographer. 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. In any case, the Allies overestimated the Germans' abilities to conduct aerial surveillance, so many of the props were never constructed. Patton was photographed visiting the props that were mocked up on regular occasions.
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 channelled through the London Controlling Section under the direction of Lieutenant-Colonel John Bevan.
Fortitude South II
On 20 July Ops (B) took over control of Fortitude South from R Force. Earlier in the previous month, they had begun work on a follow up to the operation. Their new story centred on the idea that Eisenhower had decided to defeat the Germans through the existing beachhead. As a result, elements of FUSAG had been detached and sent to reinforce Normandy and instead a second, smaller, Second American Army Group (SUSAG) would be formed to threaten the Pas-de-Calais.
The plan met some criticism; first of all, there was opposition to the creation of so many fictional US formations in the face of a known manpower shortage in America. Secondly, the plan reduced the threat to Pas-de-Calais and so the Fifteenth Army might be moved to reinforce Normandy. As with its predecessor, in late June Strangeways re-wrote the operation to ensure the focus remained on Calais.
By 28 September 1944 the Allies had agreed to end the Fortitude deception, moving to operational deceptions in the field under the overall charge of Ops (B).
The Allies were able to judge how well Fortitude was working thanks to Ultra, signals intelligence obtained by breaking German codes and cyphers. On June 1st a decrypted transmission by Hiroshi Ōshima (the Japanese ambassador) to his government recounting a recent conversation with Hitler confirmed the effectiveness of Fortitude.
They maintained the pretence 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.
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.
Reasons for success
The operation was successful for several reasons:
The long term view was taken by British Intelligence to cultivate double agents as channels of disinformation to the enemy.
The use of Ultra decrypts of machine-encrypted messages between the 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 amid the various elements.
General George S. Patton was the leader the Germans feared the most, and they considered him the Allies' best general. Therefore, the German High Command believed he would lead the attack.
From early 1942, Tirpitz posed a significant threat to the Allied convoys transporting supplies through the Norwegian Sea to the Soviet Union. Stationed in fjords on the Norwegian coast, the battleship was capable of overwhelming the close-escort forces assigned to the Arctic convoys or breaking out into the North Atlantic. To counter this threat, the Allies needed to keep a powerful force of warships with the British Home Fleet, and capital ships accompanied most convoys part of the way to the Soviet Union.
Tirpitz was repeatedly attacked by British forces over several years. RAF heavy bombers made four unsuccessful raids on the battleship between January and April 1942 while she was stationed at Fættenfjord. From March 1943, Tirpitz was based at Kaafjord in the far north of Norway. During Operation Source on 22 September, she was severely damaged by explosives placed on her hull by Royal Navy personnel who had used midget submarines to penetrate Kaafjord. On 3 April 1944, aircraft flying from Royal Navy aircraft carriers attacked Tirpitz during Operation Tungsten and inflicted further damage. A series of subsequent aircraft carrier attacks were unsuccessful, including Operation Mascot on 17 July and Operation Goodwood which was conducted between 22 and 29 August 1944.
As it was believed that further aircraft carrier raids would be fruitless due to shortcomings with the Royal Navy's aircraft and their armament, responsibility for sinking Tirpitz was transferred to the RAF's Bomber Command. On 15 September 1944, the elite Nos. 9 and 617 Squadrons attacked the battleship at Kaafjord during what was designated Operation Paravane. This operation employed Avro Lancaster heavy bombers armed with Tallboy heavy bombs and "Johnnie Walker" mines. The Tallboy bomb weighed 12,000 pounds and had been developed to destroy heavily armoured targets. When dropped from a high altitude, the bomb could penetrate a battleship's deck armour before exploding within the vessel. Tirpitz was struck by a single Tallboy during the attack, which caused extensive damage to her bow and rendered her unfit for combat.
As Tirpitz could not be repaired and Soviet forces were advancing towards Kaafjord, Grand Admiral Karl Dönitz, the commander of the Kriegsmarine, ordered that she be transferred to near the northern Norwegian town of Tromsø and used as an immobile battery to defend the area from attack. Dönitz hoped that this would also convince the Allies that Tirpitz continued to pose a threat. An anchorage was selected just off the coast of the island of Håkøya where it was believed the water was shallow enough to prevent the battleship from sinking if she was attacked again. Tirpitz arrived there on 16 October. The depth of water at the mooring was found to be greater than anticipated, leaving the battleship vulnerable to capsizing. Due to the space needed by Tirpitz's torpedo nets, it was not possible to move her closer to shore.
British reconnaissance aircraft located Tirpitz at Tromsø on 18 October. As the Allied intelligence services had not been able to confirm that the battleship had been crippled, it was considered necessary to conduct further air raids against her. Nos. 9 and 617 Squadrons attacked Tirpitz on 29 October in what was designated Operation Obviate. As the Tromsø area was within range of RAF bases in northern Scotland if the Lancasters were modified, this attack was somewhat simpler to conduct than Operation Paravane. To extend their range, the Lancasters were fitted with extra fuel tanks and more powerful engines, and their forward and mid-upper gun turrets and pilot's armour plate were removed. The reduction in armament left the Lancasters very vulnerable to German fighter aircraft, and they would have to fly without escort as no British fighters had the range needed to reach Tromsø.
During Operation Obviate, the bombers flew north over the Norwegian Sea, and met up over Torneträsk lake in Northern Sweden. This violated Sweden's neutrality, but allowed the bombers to approach Tromsø from the south-east, which it was believed the Germans would not expect. Despite clear weather for most of the flight, Tirpitz was covered by cloud shortly before the Lancasters reached the point where they were to release their Tallboy bombs. This made it impossible to accurately target the battleship, and while 33 aircraft bombed no hits were achieved. Tirpitz was slightly damaged by a near miss. One of the Lancasters made a forced landing in Sweden after being damaged by anti-aircraft gunfire, and the remainder returned to base.
Bomber Command remained determined to sink Tirpitz as soon as possible, and preparations for another attack began shortly after Operation Obviate. A report issued by the Royal Navy's Naval Intelligence Division on 3 November judged that it remained necessary to attack Tirpitz in northern Norway as the battleship could potentially be repaired and made fully operational if she was left unmolested and able to reach a major base. As it would be difficult to target the battleship during the period of perpetual darkness in the northern winter, further attacks needed to be made within the 23 days before this commenced. No. 5 Group RAF directed on 3 November that the next attack on Tirpitz was to take place on 5 November, and would re-use the plans developed for Operation Obviate. The raid was designated Operation Catechism.
Two de Havilland Mosquito meteorological aircraft were stationed at RAF Sumburgh from 4 November, from where they conducted daily sorties to monitor weather conditions in the Tromsø area. On the same day, twenty No. 9 Squadron and nineteen No. 617 Squadron Lancasters were dispatched to airfields in northern Scotland in preparation for the operation. A gale warning was issued that night, however, and the raid was cancelled as a result on the morning of 5 November. Both squadrons returned to their home bases during the day. The two squadrons deployed again to Scotland on 7 November, but soon returned to their home bases when the attack was cancelled.
On 10 November the Lancaster crews were briefed for another attack on Tirpitz. Both squadrons moved to northern Scotland on 11 November in response to meteorological reports which indicated that there would be clear weather over Tromsø for up to two days. The aircraft were split between RAF Kinloss, RAF Lossiemouth and RAF Milltown.
Tirpitz's defences were improved after Operation Obviate. Additional anti-aircraft guns were emplaced in the Tromsø area and torpedo nets were laid around the battleship. These augmented the protection offered by the anti-aircraft ships Nymphe and Thetis and several anti-aircraft batteries on the shore. Dredging operations to reduce the water level below the battleship's hull began on 1 November. By 12 November these were half complete. The smoke generators which had previously protected Tirpitz at Kaafjord were still being installed at the time of Operation Catechism and were not yet operational. In their place, seven fishing boats fitted with smoke generators were stationed near the battleship; these were not capable of generating a smokescreen which could completely cover Tirpitz.
The battleship's crew continued regular training exercises, and remained concerned about further air attacks. On 4 November Tirpitz's commanding officer Captain Wolf Junge departed. He was replaced by the executive officer, Captain Robert Weber. Weber believed that within three weeks the days would be short enough to prevent further air attacks. On 12 November around 1,700 men were on board Tirpitz.
A force of 38 fighters was transferred to Bardufoss after Operation Obviate to bolster the Tromsø region's air defences. These aircraft formed part of Jagdgeschwader 5, and were under the temporary command of Major Heinrich Ehrler. The unit had been evacuated from Kirkenes in the far northeastern region of Norway as Soviet forces advanced towards the town, and was disorganised at the time of Operation Catechism. Most of the pilots at Bardufoss were inexperienced and ill-trained, and the unit had not been properly briefed on Tirpitz's presence in the area. Ehrler arrived at Bardufoss on 9 November en-route to Alta, and decided to remain there until the morning of 12 November to oversee an emergency training programme for the fighter pilots.
The decision to launch Operation Catechism was made in the early hours of 12 November. A weather forecast issued on the afternoon of 11 November predicted that clouds might be encountered over northern Norway. One of the Mosquito meteorological aircraft flew over the area that evening, and its crew reported encountering patches of cloud when they returned to Scotland shortly after midnight on the night of 11/12 November. Nevertheless, the commander of No. 5 Group, Air Commodore Ralph Cochrane, decided to attempt another attack in the hope that the bombers would encounter clear weather over Tromsø. The plan for this operation remained the same as that used in Operation Obviate, with the attack force to use identical routes.
A total of 32 Lancasters were dispatched. No. 617 Squadron contributed eighteen, and No. 9 Squadron thirteen. As with Operations Paravane and Obviate, they were joined by a Lancaster fitted out as a film aircraft from No. 463 Squadron RAAF. The role of this aircraft was to collect material for use in propaganda films. Seven No. 9 Squadron Lancasters, including that of its commanding officer Wing Commander James Bazin, were unable to participate, as they could not be cleared in time of the snow and ice which had formed on them overnight. The No. 617 Squadron aircraft took off between 2:59 and 3:25 am BST, and the No. 9 Squadron aircraft between 3:00 and 3:35 am BST. The aircraft flown by No. 9 Squadron's deputy commander, Squadron Leader Bill Williams, was among those able to take off and he assumed command of the unit.
The Lancasters flew individually over the Norwegian Sea. As had also been the case during Operation Obviate, they crossed the Norwegian coast between the towns of Mosjøen and Namos where a gap in the German radar coverage had been located. Several of the bombers flew too far to the north, and came within range of German radar stations. The attack force rendezvoused over Torneträsk Lake. After making two orbits, No. 617 Squadron's commanding officer, Wing Commander Tait fired a flare gun from his aircraft to signal the force to proceed to Tromsø. Two No. 9 Squadron Lancasters failed to reach Torneträsk Lake in time, and returned to base without attacking.
The attack force proceeded north-west towards Tromsø, and climbed to 14,000 feet to clear the mountains along the border of Sweden and Norway. They were guided by radio homing signals transmitted by a Norwegian Milorg agent stationed near the border between the two countries. By the time they reached the Tromsø area, both of the squadrons had formed up into loose formations. No. 617 Squadron led the attack, followed by No. 9 Squadron. The Lancasters were grouped into "gaggles" of four to six aircraft which flew at altitudes of between 14,000 feet and 15,000 feet. The No. 463 Squadron film aircraft approached Tromsø at 6,000 feet, and dropped to 2,000 feet to evade anti-aircraft fire at the start of the attack.
The German forces in the Tromsø area failed to adequately respond to multiple warnings of the approaching British bombers. Between 7:39 am and 8:50 am local time several reports of Lancasters in the area were received from observation posts. As the first aircraft to be spotted were flying east, it was thought that they might be headed to the Soviet Union. Tirpitz was not notified of the reports until 8:15 am local time, and few reports were passed on to the JG 5 detachment at Bardufoss. Tirpitz's air raid siren was sounded at 8:51 am, and Weber informed her crew seven minutes later that an attack was possible.
At around 9:15 am local time Tirpitz contacted Bardufoss to request that fighters be dispatched to provide air cover. This was too late for any of the fighters to reach Tromsø before the bombers arrived. The local Luftwaffe command ordered the fighters to be scrambled at 9:18 am. Due to various delays, the aircraft did not begin taking off from Bardufoss until approximately 9:32 am. Ehrler took off first, but the others were delayed from doing so for several minutes while an aircraft landed on the runway. Ehrler proceeded to the Tromsø area by himself, but was unable to locate the British bombers before they attacked. It is not clear where the other fighters were dispatched to, as one post-attack report states they were sent to the border with Sweden, another that they proceeded to Kaafjord and two pilots claimed to have reached Tromsø after Tirpitz was destroyed.
Weather conditions over Tromsø continued to be clear when the attack force arrived in the area. Tait spotted Tirpitz from 20 miles away, and later recalled that she was "lying squat and black among her torpedo nets like a spider in her web, silhouetted against the glittering blue and green waters of the fjord".
Tirpitz fired the first shots of the battle at 9:38 am BST when she opened fire on the bombers with her 380-millimetre calibre main guns from a range of 13.5 miles. Other anti-aircraft guns also fired on the Lancasters as they approached, but did not disrupt them. No smokescreen was present as they flew north-west towards their bombing positions.
The attack commenced at 9:41 am BST. Tait's aircraft was the first to drop its Tallboy, which hit Tirpitz. No. 617 Squadron completed its attack at 9:44 am BST with all aircraft bombing. No. 9 Squadron aircraft began dropping their Tallboys at 9:45 am BST. By this time the battleship was on fire and covered in smoke. The last bomb was released at 9:49 am BST.
Tirpitz was rapidly destroyed. She was struck by two Tallboys which penetrated her armoured deck. One hit to the port of "Bruno" turret in the forward section of the ship but did not explode. The other, which was dropped by Tait's aircraft, struck the port side amidships near the tracks for the aircraft catapult and exploded over the port boiler room. This explosion caused severe damage which resulted in extensive flooding, fires throughout the ship and a list of 15 to 20 degrees to port. Several other bombs detonated in the water near Tirpitz, which caused further damage to her hull and additional flooding. These explosions also created large craters below the ship, and blew away much of the gravel which had been dumped beneath her. Almost all the hits and near misses were on the port side of Tirpitz, which destabilised her and led the list to rapidly increase. Many sailors manning Tirpitz's anti-aircraft guns were killed or wounded by the bombs, resulting in a significant reduction in the volume of fire directed at the Lancasters.
After the first bomb struck his ship Weber ordered the crew to evacuate the armoured citadel and attempt to counter the flooding. Despite the list, Weber expected that Tirpitz would not sink as the water beneath her hull was too shallow. Counter-flooding proved impossible, as the controls for the necessary systems had been abandoned and the volume of water which was entering the ship was well beyond their ability to fight had they been operational. Weber ordered that the lower decks be evacuated at 9:45 am, by which time the list had reached between 30 and 40 degrees. At 9:50 am the magazine for "Caesar" turret exploded, causing extensive damage. Tirpitz's list rapidly increased, and she was soon lying on her side. Weber then gave the order to abandon ship. The battleship continued to heel over, and capsized at 9:52 am. Almost 1,000 of her crew had either been killed by this time, or were trapped inside the hull.
The crews of several Lancasters observed Tirpitz capsize. The No. 463 Squadron film aircraft made a final pass over the battleship at an altitude of just 50 feet to capture footage of the event. Just after 11:00 am BST a photo-reconnaissance Mosquito overflew the Tromsø region, and photographed the wreck. The Secret Intelligence Service agent Egil Lindberg also sent radio reports from Tromsø confirming that Tirpitz had been destroyed.
Tirpitz following Operation Catechism
The German forces in the Tromsø area endeavoured to rescue the surviving members of Tirpitz's crew. Within two hours, 596 had swum to shore or been rescued from the water. Others were trapped in air pockets within the wreck. These sailors were doomed unless they were able to move to the former bottom of the ship and be rescued before their air supply ran out. Shortly after Tirpitz capsized, parties of sailors climbed onto the hull and painted marks on locations were they heard signs of life. Acetylene torches were needed to cut into the thick hull, and none were initially available. Local Norwegian civilians who owned torches hid them, and only one could be found. A total of 87 sailors were rescued from within the hull in the 24 hours after the attack. Cutting continued for two further days, and was finally abandoned when it was assessed that the oxygen supply inside the wreck would have been exhausted; no survivors were recovered during this period. Estimates of the total number of sailors killed vary, with the most common figures lying between 940 and 1,204. Weber and all of his senior officers were among the dead.
Many Norwegian civilians in Tromsø were pleased that Tirpitz had been destroyed, not least as it meant the end of an order requiring that they billet members of her crew. Several civilians who showed pleasure at the event in public were arrested by the Gestapo. However, other Norwegians were saddened by the way in which the battleship's crew had died.
Work began on stripping Tirpitz's wreck soon after rescue efforts ended, and continued until the late 1950s. Prior to the end of the war German personnel removed the ships' brass propellers so they could be melted down, as well as some other components. The wreck was sold to a Norwegian scrap dealing company in 1948, and was broken up in situ. Salvage work concluded in 1957, by which time most of the battleship had been removed. The bodies of German sailors recovered from the wreck by scrappers were initially buried alongside unwanted parts of Tirpitz, but this ceased following complaints by a local church minister. The hundreds of other bodies which were recovered were buried in cemeteries.
Following the Allied invasion of Normandy on June 6th 1944, progress inland was to become very slow. To facilitate the Allied build-up in France and to secure room for further expansion, the deep water port of Cherbourg on the western flank of the American sector and the historic town of Caen in the British and Canadian sector to the east, were early objectives. The original plan for the Normandy campaign envisioned strong offensive efforts in both sectors, in which the Second Army would secure Caen and the area south of it and the First US Army would "wheel round" to the Loire.
General Sir Bernard Montgomery—commanding all Allied ground forces in Normandy—intended Caen to be taken on D-Day, while Cherbourg was expected to fall 15 days later. The Second Army was to seize Caen and then form a front to the southeast, extending to Caumont, to acquire airfields and protect the left flank of the First US Army as it moved on Cherbourg. Possession of Caen and its surroundings would also give the Second Army a suitable staging area for a push south to capture Falaise, which could be used as the pivot for a swing east to advance on Argentan and then the Touques River. The capture of Caen has been described by the British official historian Lionel Ellis as the most important D-Day objective assigned to the British I Corps. Ellis and Chester Wilmot called the Allied plan "ambitious" since the Caen sector contained the strongest defences in Normandy.
The initial attempt by I Corps to reach the city on D-Day was blocked by elements of the 21st Panzer Division and with the Germans committing most of the reinforcements sent to meet the invasion to the defence of Caen, the Anglo-Canadian front rapidly congealed short of the Second Army's objectives. Operation Perch in the week following D-Day and Operation Epsom brought some territorial gains and depleted its defenders but Caen remained in German hands until Operation Charnwood, when the Second Army managed to take the northern part of the city up to the River Orne in a frontal assault.
The successive Anglo-Canadian offensives around Caen kept the best of the German forces in Normandy, to the eastern end of the Allied lodgement but even so the First US Army made slow progress against dogged German resistance. In part, operations were slow due to the constraints of the bocage landscape of densely packed banked hedgerows, sunken lanes and small woods, for which U.S. units had not trained. With no ports in Allied hands, all reinforcement and supply had to take place over the beaches via the two Mulberry harbours and was at the mercy of the weather. On 19 June, a severe storm descended on the English Channel, lasting for three days and causing significant delays to the Allied build-up and the cancellation of some operations. The First US Army advance in the western sector was eventually halted by Bradley before the town of Saint-Lô, to concentrate on the seizure of Cherbourg. The defence of Cherbourg consisted largely of four German battlegroups formed from the remnants of units that had retreated up the Cotentin peninsula but the port defences had been designed principally to meet an attack from the sea. Organized German resistance ended only on 27 June, when the 9th US Infantry Division managed to reduce the defences of Cap-de-la-Hague, north-west of the port. Within four days, VII Corps resumed the offensive toward Saint-Lô, alongside XIX Corps and VIII Corps, causing the Germans to move more armour into the U.S. sector.
The originator of the idea for Operation Cobra is disputed. According to Montgomery's official biographer, the foundation of Operation Cobra was laid on 13 June. Planning was immensely aided by detailed Ultra intelligence which supplied up-to-date decodes of communications between Oberkommando der Wehrmacht (OKW, the German armed forces high command) and Hitler's generals. Montgomery's plan at that time called for the U.S. First Army to take Saint-Lô and Coutances and then make two southward thrusts; one from Caumont toward Vire and Mortain and the other from Saint-Lô toward Villedieu and Avranches. Although pressure was to be kept up along the Cotentin Peninsula towards La Haye-du-Puits and Valognes, the capture of Cherbourg was not the priority. With the capture of Cherbourg by VII Corps on 27 June, Montgomery's initial timetable was overtaken by events and the thrust from Caumont was never adopted.
Following the conclusion of Operation Charnwood and the cancellation of the First Army offensive towards Saint-Lô, Montgomery met with Bradley and Dempsey on 10 July to discuss plans for the 21st Army Group. Bradley said that progress on the western flank was very slow but that plans had been laid for another breakout attempt, codenamed Operation Cobra, to be launched by the First Army on 18 July. Montgomery approved the plan and that the strategy would remain the diversion of German attention from the First Army to the British and Canadian sector. To accomplish this, Operation Goodwood was planned and Eisenhower ensured that both operations would have the support of the Allied strategic bombers.
On 12 July, Bradley briefed his commanders on the Cobra plan, which consisted of three phases. The main effort would be under the control of VII Corps. In the first phase, the breakthrough attack would be conducted by the 9th Infantry Division and the 30th Infantry Division, which would break into the German defensive zone and then hold the flanks of the penetration while the 1st Infantry Division and 2nd Armoured Division pushed into the depth of the position until resistance collapsed. The 1st Infantry Division "was to take Marigny, with this objective exploited by a stream of General Watson's 3rd Armoured Division armour that would move south toward Coutances". The 2nd Armoured Division—part of "Collins' exploitation force" of the 2nd Armoured Division in the east of the VII Corps sector and the "1st Infantry Division reinforced by Combat Command B of the 3rd Armoured division in the west"—would "pass through the 30th Infantry Division sector ... and guard the overall American left flank." If VII Corps succeeded, the western German position would become untenable, permitting a relatively easy advance to the southwest end of the bocage to cut off and seize the Brittany peninsula. First Army intelligence estimated that no German counterattack would occur in the first few days after Cobra's launch and that if they did later, they would be no more than battalion-sized operations.
Cobra was to be a concentrated attack on a 6,400m front, unlike previous American broad front offensives and would have a mass of air support. Fighter-bombers would concentrate on hitting forward German defences in a 230m belt immediately south of the Saint-Lô–Periers road, while General Spaatz's heavy bombers would bomb to a depth of 2,300 m behind the German main line of resistance. It was anticipated that the physical destruction and shock value of a short, intense preliminary bombardment would greatly weaken the German defence so in addition to divisional artillery, Army- and Corps-level units would provide support, including nine heavy, five medium and seven light artillery battalions. Over 1,000 divisional and corps artillery pieces were committed to the offensive and approximately 140,000 artillery rounds were allocated to the operation in VII Corps, with another 27,000 for VIII Corps.
To overcome the constraints of the bocage that had made attacks so difficult and costly for both sides, Rhino modifications were made to some M4 Sherman, M5A1 Stuart tanks and M10 tank destroyers, by fitting them with hedge-breaching 'tusks' that could force a path through hedgerows. German tanks remained restricted to the roads but U.S. armoured vehicles could manoeuvre more freely, although the effectiveness of the devices was exaggerated. By the eve of Cobra, 60 percent of the tanks of the First Army had the rhino modification. To preserve operational security, Bradley forbade their use until Cobra was launched. In all, 1,269 M4 medium tanks, 694 M5A1 light tanks and 288 M10 tank destroyers were available.
On 18 July, the British VIII and I Corps—to the east of Caen—launched Operation Goodwood. The offensive began with the largest air bombardment in support of ground forces yet, with more than 1,000 aircraft dropping 6,000 short tons of high explosive and fragmentation bombs from low altitude. German positions to the east of Caen were shelled by 400 artillery pieces and many villages were reduced to rubble but German artillery further to the south, on the Bourguébus Ridge, was outside the range of the British artillery and the defenders of Cagny and Émiéville were largely unscathed by the bombardment. This contributed to the losses suffered by Second Army, which sustained over 4,800 casualties. Principally an armoured offensive, between 250 and 400 British tanks were put out of action, although recent examination suggests that only 140 were completely destroyed with an additional 174 damaged. The operation remains the largest tank battle ever fought by the British Army and resulted in the expansion of the Orne bridgehead and the capture of Caen on the south bank of the Orne.
Simultaneously, the II Canadian Corps on the western flank of Goodwood began Operation Atlantic to strengthen the Allied foothold along the banks of the Orne and take Verrières Ridge to the south of Caen. Atlantic made initial gains but ran out of steam as casualties mounted. Having cost the Canadians 1,349 men and with the heavily defended ridge firmly in German hands, Atlantic was closed down on 20 July. At Montgomery's urging, "strongly underlined in the Supreme Commander's communications to Montgomery", the II Canadian Corps commander, Lieutenant-General Guy Simonds, began a second offensive a few days later, codenamed Operation Spring. This had the limited but important aim of tying down German units to prevent them from being transferred to the American sector, although Simonds took the opportunity to make another bid for Verrières Ridge. Again the fighting for Verrières Ridge proved extremely bloody for the Canadians, with 25 July marking the costliest day for a Canadian battalion—The Black Watch of Canada—since the Dieppe Raid of 1942. A counterstroke by two German divisions pushed the Canadians back past their start lines and Simonds had to commit reinforcements to stabilize the front. With Goodwood, the Canadian operations caused the Germans to commit most of their armour and reinforcements to the eastern sector. Operation Spring—despite its cost—had drawn the 9th SS Panzer Division away from the U.S. sector on the eve of Operation Cobra. Only two Panzer divisions with tanks now faced the First Army. Seven Panzer divisions with tanks were around Caen, far away from Operation Cobra as were all the heavy Tiger tank battalions and the three Nebelwerfer brigades in Normandy.
Bradley and Collins near Cherbourg
To gain good terrain for Operation Cobra, Bradley and Collins conceived a plan to push forward to the Saint-Lô–Periers road, along which VII and VIII Corps were securing jumping-off positions. On 18 July, at a cost of 5,000 casualties, the American 29th and 35th Infantry Divisions managed to gain the vital heights of Saint-Lô, driving back General der Fallschirmtruppen Eugen Meindl's II Parachute Corps. Meindl's paratroopers, together with the 352nd Infantry Division were now in ruins, and the stage for the main offensive was set. Due to poor weather conditions that had also been hampering Goodwood and Atlantic, Bradley decided to postpone Cobra for a few days—a decision that worried Montgomery, as the British and Canadian operations had been launched to support a breakout attempt that was failing to materialize. By 24 July the skies had cleared enough for the start order to be given, and 1,600 Allied aircraft took off for Normandy. However, the weather closed in again over the battlefield. Under poor visibility conditions, more than 25 Americans were killed and 130 wounded in the bombing before the air support operation was postponed until the following day. Some enraged soldiers opened fire on their own aircraft, a not uncommon practice in Normandy when suffering from friendly fire.
Operation Cobra 25–29 July 1944
After the one-day postponement, Cobra got underway at 09:38 on 25 July, when around 600 Allied fighter-bombers attacked strong points and enemy artillery along a 270 m -wide strip of ground located in the St. Lô area. For the next hour, 1,800 heavy bombers of the U.S. Eighth Air Force saturated a 6,000 yd × 2,200 yd area on the Saint-Lô–Periers road, succeeded by a third and final wave of medium bombers. Approximately 3,000 U.S. aircraft had carpet-bombed a narrow section of the front, with the Panzer-Lehr-Division taking the brunt of the attack. However, once again not all the casualties were German; Bradley had specifically requested that the bombers approach the target from the east, out of the sun and parallel to the Saint-Lô–Periers road, in order to minimize the risk of friendly losses, but most of the airmen instead came in from the north, perpendicular to the front line. Bradley, however, had apparently misunderstood explanations from the heavy bomber commanders that a parallel approach was impossible because of the time and space constraints Bradley had set. Additionally, a parallel approach would not, in any event, have assured that all bombs would fall behind German lines because of deflection errors or obscured aim points due to dust and smoke. Despite efforts by U.S. units to identify their positions, inaccurate bombing by the Eighth Air Force killed 111 men and wounded 490. The dead included Bradley's friend and fellow West Pointer Lieutenant General Lesley McNair—the highest-ranking U.S. soldier to be killed in action in the European Theatre of Operations.
By 11:00, the infantry began to move forward, advancing from crater to crater beyond what had been the German outpost line. Although no serious opposition was forecast, the remnants of Fritz Bayerlein′s Panzer Lehr—consisting of roughly 2,200 men and 45 armoured vehicles—had regrouped and were prepared to meet the advancing U.S. troops, and to the west of Panzer Lehr the German 5th Parachute Division had escaped the bombing almost intact. Collins' VII Corps were quite disheartened to meet fierce enemy artillery fire, which they expected to have been suppressed by the bombing. Several U.S. units found themselves entangled in fights against strongpoints held by a handful of German tanks, supporting infantry and 88 mm guns—VII Corps gained only 2,000 m during the rest of the day. However, if the first day's results had been disappointing, General Collins found cause for encouragement; although the Germans were fiercely holding their positions, these did not seem to form a continuous line and were susceptible to being outflanked or bypassed. Even with prior warning of the American offensive, the British and Canadian actions around Caen had convinced the Germans that the real threat lay there, and tied down their available forces to such an extent that a succession of meticulously prepared defensive positions in depth, as encountered during Goodwood and Atlantic, were not created to meet Cobra.
The St. Lô breakthrough, 25–31 July
On the morning of 26 July, the U.S. 2nd Armored Division and the 1st Infantry Division joined the attack as planned, reaching one of Cobra's first objectives—a road junction north of Le Mesnil-Herman—the following day. Also on 26 July, VIII Corps entered the battle, led by the 8th U.S. Infantry Division and 90th U.S. Infantry Division. Despite clear paths of advance through the floods and swamps across their front, both divisions initially disappointed the First Army by failing to gain significant ground but first light the next morning revealed that the Germans had been compelled to retreat by their crumbling left flank, leaving only immense minefields to delay VIII Corps. By noon on 27 July, the 9th U.S. Infantry Division was also clear of any organized German resistance and was advancing rapidly.
Breakout and advance 28–30 July
By 28 July, the German defences across the U.S. front had largely collapsed under the full weight of the VII and VIII Corps advance and resistance was disorganized and patchy. The 4th Armoured Division (VIII Corps)—entering combat for the first time—captured Coutances but met stiff opposition east of the town and U.S. units penetrating into the depth of the German positions were counter-attacked by elements of the 2nd SS Panzer Division, 17th SS Panzergrenadier Division and the 353rd Infantry Division, seeking to escape entrapment. Around Roncey, P-47 Thunderbolts of the 405th Fighter Group destroyed a German column of 122 tanks, 259 other vehicles and 11 artillery pieces. An attack by British Typhoons close to La Baleine destroyed 9 tanks, 8 other armoured vehicles and 20 other vehicles. A counter-attack was mounted against the U.S. 2nd Armoured Division by German remnants but this was a disaster and the Germans abandoned their vehicles and fled on foot. Two columns of the 2nd SS Panzer Division were mauled by the U.S. 2nd Armoured Division. A column around La Chapelle was bombarded at point blank range by 2nd Armoured Division artillery. In two hours, American artillery fired over 700 rounds, into the column. The Germans suffered the loss of 50 dead, 60 wounded and 197 taken prisoner. Material losses were over 260 German combat vehicles destroyed. Beyond the town another 1,150 German soldiers were killed and the Germans lost 96 armoured combat vehicles and trucks. The U.S. 2nd Armoured Division destroyed 64 German tanks and 538 other German combat vehicles during Operation Cobra. The U.S. 2nd Armoured Division suffered 49 tank losses in the process. The 2nd Armoured Division also inflicted over 7,370 casualties on the Germans while suffering 914 casualties. At the beginning of Operation Cobra the German Panzer Lehr Division had only 2,200 combat troops, 12 Panzer IV and 16 Panthers fit for action and 30 tanks in various states of repair behind the lines. Panzer Lehr was in the path of Allied bombing that consisted of 1,500 bombers. The division suffered about 1,000 casualties during this bombardment. An exhausted and demoralized Bayerlein reported that his Panzer Lehr Division was "finally annihilated", with its armour wiped out, its personnel either casualties or missing and all headquarters records lost.
Field Marshal Günther von Kluge Oberbefehlshaber West (commander of German forces on the Western Front)—was mustering reinforcements, and elements of the 2nd Panzer Division and the 116th Panzer Division were approaching the battlefield. The U.S. XIX Corps entered the battle on 28 July on the left of VII Corps and between 28 and 31 July became embroiled with these reinforcements in the fiercest fighting since Cobra began. During the night of 29/30 July near Saint-Denis-le-Gast, to the east of Coutances, elements of the 2nd Armoured Division found themselves fighting for their lives against a German column from the 2nd SS Panzer Division and 17th SS Panzergrenadier Division, which passed through the American lines in the darkness. Other elements of the 2nd Armoured Division were attacked near Cambry and fought for six hours; Bradley and his commanders knew that they were dominating the battlefield and such desperate assaults were no threat to the American position. When ordered to concentrate his division, Colonel Heinz Günther Guderian the senior staff officer of the 116th Panzer Division was frustrated by the high level of Allied fighter-bomber activity. Without receiving direct support from the 2nd Panzer Division as promised, Guderian stated that his panzergrenadiers could not succeed in a counterattack against the Americans. Advancing southward along the coast, later that day, the U.S. VIII Corps seized the town of Avranches—described by historian Andrew Williams as "the gateway to Brittany and southern Normandy"—and by 31 July XIX Corps had thrown back the last German counterattacks after fierce fighting, inflicting heavy losses in men and tanks. The American advance was now relentless, and the First Army was finally free of the bocage.
Operation Bluecoat, 30 July – 7 August
On 30 July, to protect Cobra's flank and prevent the disengagement and relocation of further German forces, VIII Corps and XXX Corps of the Second Army began Operation Bluecoat southwards from Caumont toward Vire and Mont Pinçon. Bluecoat kept German armoured units fixed on the British eastern front and continued the wearing down of the strength of German armoured formations in the area. The breakthrough in the centre of the Allied front surprised the Germans, when they were distracted by the Allied attacks at both ends of the Normandy bridgehead. By the time of the American breakout at Avranches, there was little to no reserve strength left for Unternehmen Lüttich, which had been defeated by 12 August, leaving the 7th Army with no choice but to retire rapidly east of the Orne river, with a rear guard of the remaining armoured and motorized units, to allow time for the surviving infantry to reach the Seine. After the first stage of the withdrawal beyond the Orne, the manoeuvre collapsed for a lack of fuel, Allied air attacks and the constant pressure of the Allied armies, culminating in the encirclement of German forces in the Falaise pocket.
The U.S. advance following Cobra was extraordinarily rapid. Between 1 August and 4 August, seven divisions of Patton's Third Army had swept through Avranches and over the bridge at Pontaubault into Brittany. The Westheer (German army in the west) had been reduced to such a poor state by the Allied offensives that, with no prospect of reinforcement in the wake of Operation Bagration, the Soviet summer offensive against Army Group Centre, very few Germans believed they could now avoid defeat. Rather than order his remaining forces to withdraw to the Seine, Adolf Hitler sent a directive to von Kluge demanding "an immediate counterattack between Mortain and Avranches" (Unternehmen Lüttich) to "annihilate" the enemy and make contact with the west coast of the Cotentin peninsula. Eight of the nine Panzer divisions in Normandy were to be used in the attack but only four (one of them incomplete) could be relieved from their defensive tasks and assembled in time. German commanders immediately protested that such an operation was impossible given their remaining resources but these objections were overruled and the counter-offensive, commenced on 7 August around Mortain. The 2nd, 1st SS and 2nd SS Panzer Divisions led the assault, although with only 75 Panzer IVs, 70 Panthers and 32 self-propelled guns. Hopelessly optimistic, the offensive was over within 24 hours, although fighting continued until 13 August.
By 8 August, the city of Le Mans—the former headquarters of the German 7th Army—had fallen to the Americans.
On 14 August, in conjunction with American movements northward to Chambois, Canadian forces launched Operation Tractable; the Allied intention was to trap and destroy the German 7th Army and 5th Panzer Army near the town of Falaise. Five days later, the two arms of the encirclement were almost complete; the advancing U.S. 90th Infantry Division had made contact with the Polish 1st Armoured Division and the first Allied units crossed the Seine at Mantes Gassicourt, while German units were fleeing eastward by any means they could find. By 22 August, the Falaise Pocket—which the Germans had been fighting desperately to keep open to allow their trapped forces to escape—was finally sealed, ending the Battle of Normandy with a major Allied victory. All German forces west of the Allied lines were now dead or in captivity and although perhaps 100,000 German troops escaped they left behind 40,000–50,000 prisoners and over 10,000 dead. A total of 344 tanks and self-propelled guns, 2,447 soft-skinned vehicles and 252 artillery pieces were found abandoned or destroyed in the northern sector of the pocket. The Allies were able to advance freely through the undefended territory and by 25 August all four Allied armies (First Canadian, Second British, First U.S., and Third U.S.) involved in the Normandy campaign were on the river Seine.
The raid was requested by members of the Danish resistance movement to free imprisoned members and to destroy the records of the Gestapo, to disrupt their operations. The RAF initially turned down the request as too risky, due to the location in a crowded city centre and the need for low-level bombing but they approved the raid in early 1945 after repeated requests. Once approval had been given, planning for the raid took several weeks; scale models of the target building and the surrounding city were built for use by pilots and navigators in preparation for a very low-level attack.
The attacking force consisted of Royal Air Force de Havilland Mosquito F.B.VI fighter-bombers of No. 140 Wing RAF, comprising No. 21 Squadron RAF, No. 464 Squadron RAAF, and No. 487 Squadron RNZAF. The aircraft flew in three waves of six aircraft, with two reconnaissance Mosquito B.IVs from the Royal Air Force Film Production Unit to record the results of the attack. Thirty RAF Mustang fighters gave air cover from German aircraft and these also attacked anti-aircraft guns during the raid.
The force left RAF Fersfield in the morning and it reached Copenhagen after 11:00. The raid was carried out at rooftop level and during the first attack, a Mosquito hit a lamppost, damaging its wing and the aircraft crashed into the Jeanne d'Arc School, about 1.5 km (0.93 mi) from the target, setting it on fire. Several bombers in the second and third wave attacked the school, mistaking it for their target.
On the following day, a reconnaissance plane surveyed the target to assess the results. The damage was severe, with the west wing of the six-storey building reduced nearly to ground level. The Danish underground supplied a photograph showing the building burning from end to end.
The raid had destroyed the Gestapo headquarters and records, severely disrupting Gestapo operations in Denmark, as well as allowing the escape of 18 prisoners. Fifty-five German soldiers, 47 Danish employees of the Gestapo and eight prisoners died in the headquarters building. Four Mosquito bombers and two Mustang fighters were lost and nine airmen died on the Allied side. At the Jeanne d'Arc School, 86 schoolchildren and 18 adults were killed, many of them nuns.
On 14 July 1945, remains of an unidentified male casualty were recovered from the ruins of the Shellhus and transferred to the Department of Forensic Medicine of the University of Copenhagen. This happened again four days later and the two casualties were buried in Bispebjerg Cemetery on 4 and 21 September, respectively.