The Norwegian campaign (8 April – 10 June 1940) involved the attempt by Allied forces to defend northern Norway coupled with the Norwegian military's resistance to the country's invasion by Nazi Germany in World War II. Planned as Operation Wilfred and Plan R 4, while the German attack was feared but had not yet happened, the battlecruiser HMS Renown set out from Scapa Flow for Vestfjorden with twelve destroyers on 4 April. The Royal Navy and the Kriegsmarine met at the first and second naval battles of Narvik on 10 and 13 April, and British forces conducted the Åndalsnes landings on 13 April. The main strategic reason for Germany to invade Norway was to seize the port of Narvik and guarantee the delivery of iron ore needed for German steel production. The campaign was fought until 10 June 1940 and saw the escape of King Haakon VII and Crown Prince Olav to the United Kingdom. A British, French and Polish expeditionary force of 38,000 troops landed in the north. It had moderate success but made a rapid strategic retreat after the Battle of France began in May. The Norwegian government then went into exile in London. The campaign ended with the occupation of the entirety of Norway by Germany but elements of the Norwegian military escaped and fought on overseas.
Background
=== Outbreak of World War II === Britain and France had signed military assistance treaties with Poland and two days after the German Invasion of Poland on 1 September 1939, both declared war on Nazi Germany. However, neither country mounted significant offensive operations and for several months there were no major engagements, and this period became known as the Phoney War or "Twilight War". Winston Churchill in particular wished to escalate the war into a more active phase, in contrast to Prime Minister Neville Chamberlain. During this time both sides wished to open secondary fronts. For the Allies, in particular the French, this was based on a desire to avoid repeating the trench warfare of the First World War, which had occurred on the Franco-German border. Following the outbreak of the Second World War, the Norwegian government had mobilized parts of the Norwegian Army and all but two of the Royal Norwegian Navy's warships. The Norwegian Army Air Service and the Royal Norwegian Navy Air Service were also called up to protect Norwegian neutrality from violations by the warring countries. The first such violations were the sinkings in Norwegian territorial waters of several British ships by German U-boats. In the following months, aircraft from all the belligerents violated Norwegian neutrality. And almost immediately after the outbreak of war, the British began pressuring the Norwegian government to provide them with the services of the Norwegian merchant navy, being in dire need of shipping to oppose the strength of Nazi forces. Following protracted negotiations between 25 September and 20 November 1939, the Norwegians agreed to charter 150 tankers, as well as other ships with a tonnage of 450,000 gross tons. The Norwegian government's concern for the country's supply lines played an important role in persuading them to accept the agreement.
=== The value of Norway === Norway, although neutral, was considered strategically important for both sides for several reasons. First was the importance of iron ore from Sweden – upon which Germany depended – exported through the Norwegian port of Narvik. This route was especially important in the winter months when much of the Baltic Sea was frozen over. Narvik became of greater significance to the British when it became apparent that Operation Catherine, a plan to gain control of the Baltic Sea, would not be realized. Großadmiral Erich Raeder had pointed out several times in 1939 the danger to Germany of Britain seizing the initiative and launching its own invasion in Scandinavia, for if the powerful Royal Navy had bases at Bergen, Narvik and Trondheim, the North Sea would be virtually closed to Germany, and the Kriegsmarine would be at risk even in the Baltic. Controlling Norway would also be a strategic asset in the Battle of the Atlantic. The capture of ports would create gaps in the blockade of Germany, giving access to the Atlantic Ocean. These ports would allow Germany to use its sea power effectively against the Allies. Control of Norwegian air bases would allow German reconnaissance aircraft to operate far into the North Atlantic, while German U-boats and surface ships operating out of Norwegian naval bases would be able to break the British blockade line across the North Sea and attack convoys heading to Great Britain.
Winter War
When the Soviet Union launched its attack against Finland on 30 November 1939, the Allies found themselves aligned with Norway and Sweden in support of Finland against the much larger aggressor. After the outbreak of the Winter War between Finland and the Soviet Union, Norway mobilized larger land forces than had initially been considered necessary. By early 1940 their 6th Division in Finnmark and Troms fielded 9,500 troops to defend against a potential Soviet attack, positioned mostly in the eastern regions of Finnmark. Parts of the 6th Division's forces remained in Finnmark even after the German invasion, guarding against the danger. During the Winter War, the Norwegian authorities secretly broke the country's own neutrality by sending the Finns a shipment of 12 Ehrhardt 7.5 cm Model 1901 artillery pieces and 12,000 shells, as well as allowing the British to use Norwegian territory to transfer aircraft and other weaponry to Finland. This presented an opportunity to the Allies; offering them the potential to use the invasion to also send troop support to occupy ore fields in Sweden and ports in Norway. The plan, promoted by the British General Edmund Ironside, included two divisions landing at Narvik, five battalions somewhere in mid-Norway, and another two divisions at Trondheim. The French government pushed for action to be taken to confront the Germans away from France. These developments concerned the Germans. The Molotov–Ribbentrop Pact had placed Finland within the Soviet sphere of interest, and the Germans therefore claimed neutrality in the conflict. This policy caused a rise in anti-German sentiment throughout Scandinavia, since it was commonly believed that the Germans were allied with the Soviets. Fears began to crop up in the German high command that Norway and Sweden would then allow Allied troops to transit their territory to go to Finland's aid. The proposed Allied deployments never occurred, after protests from both Norway and Sweden, when the issue of transfers of troops through their territory was suggested. With the Moscow Peace Treaty on 12 March 1940, the Finland-related Allied plans were dropped. The abandonment of the planned landings put immense French pressure on Neville Chamberlain's British government, and eventually led to the Allies laying mines off the Norwegian coast on 8 April.
Vidkun Quisling and initial German investigation
The German high command originally thought that having Norway remain neutral was in its interest. As long as the Allies did not enter Norwegian waters, there would be safe passage for merchant vessels transporting ore via Norwegian coastal waters to Germany. Großadmiral Erich Raeder, however, argued for an invasion. He believed that the Norwegian ports would be of crucial importance for Germany in a war with the United Kingdom. On 14 December 1939, Raeder introduced Adolf Hitler to Vidkun Quisling, a Nasjonal Samling former defence minister of Norway. Quisling proposed pan-Germanic cooperation between Nazi Germany and Norway. In a second meeting on 18 December, Quisling and Hitler discussed the threat of an Allied invasion of Norway. After the first meeting with Quisling, Hitler ordered the Oberkommando der Wehrmacht (OKW) to begin investigating possible invasion plans of Norway. Meeting Quisling was central in igniting Hitler's interest in bringing the country effectively under his control. The first comprehensive German plan for the occupation of Norway, Studie Nord, ordered by Hitler on 14 December, was completed by 10 January 1940. On 27 January, Hitler ordered that a new plan, named Weserübung, be developed. Work on Weserübung began on 5 February.
Altmark incident
The Altmark incident occurred in the late hours of 16 February 1940 when the Royal Navy destroyer HMS Cossack entered Norwegian territorial waters, intercepting and boarding the German auxiliary ship Altmark in the Jøssingfjorden, near the village of Jøssingfjord. Altmark had spent the prior months as a fleet oiler turned prison ship for the German cruiser Admiral Graf Spee while the latter was acting as a commerce raider in the South Atlantic. When she began the return journey to Germany, she carried 299 prisoners taken from Allied ships sunk by the Graf Spee. She rounded Scotland, then entered Norwegian territorial waters near the Trondheimsfjord, flying the Imperial Service Flag (Reichsdienstflagge). A Norwegian naval escort accompanied Altmark as she proceeded southwards, hugging the Norwegian coastline. As Altmark was nearing Bergen harbour on 14 February, the Norwegian naval authorities demanded an inspection of her cargo. International law did not ban the transfer of prisoners of war through neutral waters, and the German captain refused the inspection. This led the commander in Bergen, Admiral Carsten Tank-Nielsen, to deny Altmark access to the restricted-access harbour zone. Tank-Nielsen was overruled by his superior, Admiral Henry Diesen, and she was escorted through. Per Norwegian neutrality regulations, government ships operated by the warring countries were forbidden from such strategically important Norwegian ports. This violation of the regulations was because Diesen feared that the British would intercept Altmark if she was forced to sail further out. On 16 February, Altmark was spotted by three British aircraft. This led the Royal Navy to send one light cruiser and five destroyers that were patrolling nearby. Under the attack of two British destroyers (HMS Ivanhoe and Intrepid), Altmark fled into the Jøssingfjord. She was escorted by the Norwegian torpedo boat Skarv. She was joined later in the fjord by a second – Kjell – and the patrol boat Firern. As HMS Cossack entered the fjord at 22:20 local time, the Norwegian vessels did not intervene when the British boarded Altmark in the late hours of 16 February. The boarding action led to the freeing of 299 British prisoners of war held on the German ship. The boarding party fought in hand-to-hand combat with the crew of Altmark, killing seven German sailors. Following this, the Germans sent strong protests to Norway, and the Norwegians sent protests to Britain. While Norwegian, Swedish and American experts in international law claimed the boarding of Altmark was a violation of Norwegian neutrality, the British government argued that the incident was at the most a technical violation that had been morally justified. The whole led to the Germans speeding up their plans for an invasion of Norway. On 21 February, General Nikolaus von Falkenhorst was placed in charge of its planning and in command of the land-based forces. The official approval for the invasion and occupation of Denmark and Norway was signed by Hitler on 1 March.
Initial plans
=== Allied plans === With the end of the Winter War, the Allies determined that any occupation of Norway or Sweden would likely do more harm than good, possibly driving the neutral countries into an alliance with Germany. However, the new French prime minister, Paul Reynaud, took a more aggressive stance than his predecessor and wanted some form of action taken against Germany. Churchill was a strong agitator for action in Scandinavia because he wanted to cut Germany off from Sweden and push the Scandinavian countries to side with the United Kingdom. This initially involved a 1939 plan to penetrate the Baltic with a naval force. This was soon changed to a plan involving the mining of Norwegian waters to stop iron ore shipments from Narvik and provoke Germany into attacking Norway, where it could be defeated by the Royal Navy. It was agreed to use Churchill's naval mining plan, Operation Wilfred, designed to remove the sanctuary of Norway's coastal waterways and force transport ships into international waters, where the Royal Navy could engage and destroy them. Accompanying this would be Plan R 4, an operation where, upon almost certain German counteraction to Operation Wilfred, the Allies would then proceed to occupy Narvik, Trondheim, Bergen, and Stavanger. The planners hoped that the operation would not provoke the Norwegians to resist the Allies with armed force. The Allies disagreed over the additional Operation Royal Marine, where mines would also be placed in the Rhine River. While the British supported this operation, the French vetoed it for three months since they also depended on the Rhine and feared German air raids on their aircraft and munitions factories. Because of this delay, Operation Wilfred, originally scheduled for 5 April, was delayed until 8 April when the British agreed to undertake the Norwegian operations separately from those on the continent.
German plans
Already in low-priority planning for months, Operation Weserübung found a new sense of urgency after the Altmark incident. The goals of the invasion were to secure the port of Narvik and the coastal waterways for ore transport, and to control the country to prevent collaboration with the Allies. It was to be presented as an armed protection of Norway's neutrality. One subject debated by German strategists was the occupation of Denmark. Denmark was considered vital because its location facilitated greater air and naval control of the area. While some wanted to simply pressure Denmark to acquiesce, it was eventually determined that it would be safer for the operation if Denmark were captured by force. Another matter that caused additional reworking of the plan was Fall Gelb, the proposed invasion of northern France and the Low Countries, which would require the bulk of German forces. Because some forces were needed for both invasions, Weserübung could not occur at the same time as Gelb, and because the nights, which provided vital cover for the naval forces, were shortening as spring approached, it therefore had to be sooner. Eventually, on 2 April, the Germans set 9 April as the day of the invasion (Wesertag), and 04:15 (Norwegian time) as the hour of the landings (Weserzeit). In Norway, the German plan called for the capture of six primary targets by amphibious landings: Oslo, Kristiansand, Egersund, Bergen, Trondheim and Narvik. Additionally, supporting Fallschirmjäger (paratroops) were to capture other key locations, such as airfields at Fornebu outside Oslo and Sola outside Stavanger. The plan was designed to quickly overwhelm the Norwegian defenders and occupy these vital areas before any form of organized resistance could be mounted. The following forces were thus organized:
Gruppe 1: Ten destroyers transporting 2,000 Gebirgsjäger troops commanded by General Eduard Dietl to Narvik Gruppe 2: The heavy cruiser Admiral Hipper and four destroyers to Trondheim Gruppe 3: The light cruisers Köln and Königsberg, with several smaller support vessels to Bergen Gruppe 4: The light cruiser Karlsruhe and several smaller support vessels to Kristiansand Gruppe 5: The heavy cruisers Blücher and Lützow, the light cruiser Emden and several smaller support vessels to Oslo Gruppe 6: Four minesweepers to Egersund Additionally, the battleships Scharnhorst and Gneisenau would escort Gruppe 1 and Gruppe 2 as they travelled together, and there would also be several echelons of transports carrying additional troops, fuel and equipment. Against Denmark, two motorized brigades would capture bridges and troops; paratroops would capture Aalborg airfield in the north, and heavy fighters of the Luftwaffe would destroy the Danish aircraft on the ground. While there were also several naval task groups organized for this invasion, none of them had any large ships. Unescorted troopships would transport soldiers to capture the Danish High Command in Copenhagen. The following German naval forces used to invade Denmark were as organized:
Gruppe 7: Deutschland-class battleship Schleswig-Holstein, two transports, two minesweepers and six trawlers to land one regiment at Korsør and a company at Nyborg. Gruppe 8: One minelayer, an icebreaker and two patrol boats to land one battalion at Copenhagen. Gruppe 9: One freighter, two tugboats and seven minesweepers to land one company at Middlefart and Fredericia. Gruppe 10: One escort sloop and 20 minesweepers to land two companies from the 170th Infantry Division at Esbjerg. Gruppe 11: One minesweeper depot ship and 14 minesweepers to land a company from the 170th Infantry Division at Thyborøn. The Germans hoped they could avoid armed confrontation with the residents of both countries, and their troops were instructed to fire only if fired upon.
Opposing forces
=== German === The German forces used in the campaign were some 120,000 troops in seven divisions and one Fallschirmjäger battalion, as well as panzer and artillery units. Most of the Kriegsmarine's major units were also earmarked for the campaign. The Luftwaffe's 10th Air Corps deployed against Norway consisted of 1,000 aircraft, including 500 transport planes and 186 Heinkel He 111 bombers.
=== Norwegian and Allied === The Norwegian Armed Forces fielded around 55,000 combatants involved in the fighting, including 19,000 soldiers, mainly in six infantry divisions. The Norwegian Army had around 60,000 trained soldiers, with 3,750 troops per regiment. However, due to the Germans' speed and surprise, only 52,000 ever saw combat. The Allied expeditionary force numbered around 38,000 men.
German invasion
Fleet movements
The German invasion began on 3 April 1940, when covert supply vessels began to head out in advance of the main force. The Allies initiated their plans on the following day, with 16 Allied submarines ordered to the Skagerrak and Kattegat to serve as a screen and give advance warning of a German response to Operation Wilfred, which was launched the following day when Rear-Admiral William Whitworth, Rear-Admiral Commanding, Battlecruiser Squadron, in HMS Renown set out from Scapa Flow for the Vestfjorden with twelve destroyers. On 7 April, bad weather began to develop in the region, blanketing the area with thick fog and causing rough seas, making travel difficult. Renown's force was soon caught in a heavy snowstorm, and HMS Glowworm, one of the destroyer escorts, had to drop out of formation to search for a man swept overboard. The weather aided the Germans, providing a screen for their forces, and in the early morning they sent out Gruppe 1 and Gruppe 2, which had the longest distance to travel. Although the weather did make reconnaissance difficult, the two German groups were discovered 170 km (110 mi) south of the Naze (the southernmost part of Norway) slightly after 08:00 by Royal Air Force (RAF) patrols and reported as one cruiser and six destroyers. A trailing squad of bombers sent out to attack the German ships found them 125 km (78 mi) farther north than they had been before. No damage was inflicted by the attack, but the German group's strength was reassessed as being one battlecruiser, two cruisers and ten destroyers. Because of a strict enforcement of radio silence, the bombers were not able to report this until 17:30. On learning of the German movement, the Admiralty came to the conclusion that the Germans were attempting to break the blockade that the Allies had placed on Germany and use their fleet to disrupt Atlantic trade routes. Admiral Sir Charles Forbes, Commander-in-Chief of the British Home Fleet, was notified of this and set out to intercept them at 20:15. With both sides unaware of the magnitude of the situation, they proceeded as planned. Renown arrived at the Vestfjord late that night and maintained position near the entrance while the minelaying destroyers proceeded to their task. Meanwhile, the Germans launched the remainder of their invasion force. The first direct contact between the two sides occurred the next morning without either side's intention. Glowworm, on her way to rejoin Renown, happened to come up behind Z11 Bernd von Arnim and then Z18 Hans Lüdemann in the heavy fog around 08:00 on 8 April. Immediately a skirmish broke out and the German destroyers fled, signalling for help. The request was soon answered by Admiral Hipper, which quickly crippled Glowworm. During the action, Glowworm rammed Admiral Hipper. Significant damage was done to Admiral Hipper's starboard side, and Glowworm sank. During the fight Glowworm had broken radio silence and informed the Admiralty of her situation. She was not able to complete her transmission though, and all the Admiralty knew was that Glowworm had been confronted by a large German ship, shots were fired, and contact with the destroyer could not be re-established. In response, the Admiralty ordered Renown and her single destroyer escort (the other two had gone to friendly ports for fuel), to abandon her post at the Vestfjord and head to Glowworm's last known location. At 10:45, the remaining eight destroyers of the minelaying force were ordered to join them as well. On the morning of 8 April, the Polish submarine ORP Orzeł sank the clandestine German troop transport ship Rio de Janeiro off the southern Norwegian port of Lillesand. Discovered among the wreckage were uniformed German soldiers and military supplies. Though Orzeł reported the incident to the Admiralty, they were too concerned by the situation with Glowworm and the presumed German breakout to give it much thought and did not pass the information on. Many of the German soldiers from the wreck were rescued by Norwegian fishing boats and the destroyer Odin. On interrogation the survivors disclosed that they were assigned to protect Bergen from the Allies. This information was passed on to Oslo, where the Norwegian Parliament ignored the sinking due to being distracted by the British mining operations off the Norwegian coast. At 14:00, the Admiralty received word that aerial reconnaissance had located a group of German ships a considerable distance west-northwest of Trondheim, bearing west. This reinforced the notion that the Germans were indeed intending a breakout, and the Home Fleet changed direction from northeast to northwest to again try to intercept. Additionally, Churchill cancelled Plan R 4 and ordered the four cruisers carrying the soldiers and their supplies to disembark their cargo and join the Home Fleet. In fact, the German ships, Gruppe 2, were only performing delaying circling manoeuvres to approach their destination of Trondheim at the designated time. That night, after learning of numerous sightings of German ships south of Norway, Charles Forbes began to doubt the validity of the breakout idea, and he ordered the Home Fleet to head south to the Skagerrak. He also ordered Repulse, along with another cruiser and a few destroyers, to head north and join Renown. At 23:00, as Forbes was just learning of the incident with Orzeł, Gruppe 5 was confronted by the Norwegian patrol vessel Pol III at the entrance to the Oslofjord. Pol III quickly sent an alarm to the coastal batteries on Rauøy (Rauøy island) and opened fire on the torpedo boat Albatros with her single gun shortly before colliding with it. Albatros and two of her companions responded with anti-aircraft fire, killing the Norwegian captain and setting Pol III on fire. Gruppe 5 continued into the Oslofjord and cleared the outer batteries without incident. Several of the smaller German ships then broke off to capture the bypassed fortifications along with Horten. This activity did not go unnoticed, and soon reports had reached Oslo, leading to a midnight session of the Norwegian cabinet. At this meeting, the cabinet issued orders for the mobilization of four of the six field brigades of the Norwegian Army. The members of the cabinet failed to understand that the partial mobilization they had ordered would, according to the regulations in place, be carried out in secret and without public declaration. Troops would be issued their mobilization orders by post. The only member of the cabinet with in-depth knowledge of the mobilization system, Defence Minister Birger Ljungberg, failed to explain the procedure to his colleagues. He would later be heavily criticized for this oversight, which led to unnecessary delays in the Norwegian mobilization. Prior to the cabinet meeting, Ljungberg had dismissed repeated demands for a total and immediate mobilization, made by the chief of the general staff, Rasmus Hatledal. Hatledal had approached Ljungberg on 5, 6 and 8 April, asking the defence minister to request the cabinet issue orders for mobilization. The issue had been discussed in the evening of 8 April, after the commanding general, Kristian Laake, had joined the calls for a mobilization. At that time the mobilization had been limited to two field battalions in Østfold, further delaying the larger-scale call-up of troops. When Laake's call for mobilization was finally accepted sometime between 03:30 and 04:00 on 9 April, Laake assumed, like Defence Minister Ljungberg, that the cabinet knew that they were issuing a partial and silent mobilization. The poor communication between the Norwegian armed forces and the civilian authorities caused much confusion in the early days of the German invasion. At about this time, further north, Renown was heading back to Vestfjord after reaching Glowworm's last known location and not finding anything. Heavy seas had caused Whitworth to sail further north than normal, and he was separated from his destroyers when he encountered Scharnhorst and Gneisenau. Renown engaged the two battlecruisers off the Lofoten Archipelago, and during the short battle Renown scored several hits on the German vessels, forcing them to flee north. Renown attempted to pursue, but the German warships used their superior speed to escape.
Weserzeit
In the Ofotfjord leading to Narvik, the ten German destroyers of Gruppe 1 made their approach. With Renown and her escorts earlier diverted to investigate the Glowworm incident, no British ships stood in their way, and they sailed into the area unopposed. By the time they had reached the inner area near Narvik, most of the destroyers had peeled off from the main formation to capture the outer batteries of the Ofotfjord, leaving only three to contend with the two old Norwegian coastal defence ships standing guard in Narvik harbour, Eidsvold and Norge. Although antiquated, the two coastal defence ships were quite capable of taking on the much more lightly armed and armoured destroyers. After a quick parley with the captain of Eidsvold, Odd Isaachsen Willoch, the German ships opened fire on the coastal defence ship, sinking her after hitting her with three torpedoes. Norge entered into the fray shortly after and began to fire on the destroyers, but her marksmen were inexperienced and she did not hit the Germans ships before being sunk by a salvo of torpedoes from the German destroyers. Following the sinking of Eidsvold and Norge, the commander of Narvik, Konrad Sundlo, surrendered the land forces in the town without a fight. At Trondheim, Gruppe 2 also faced only minor resistance to their landings. In the Trondheimsfjord, Admiral Hipper engaged the defensive batteries while her destroyers sped past them at 25 knots (46 km/h). A well placed shot by Admiral Hipper severed the power cables for the searchlights and rendered the guns ineffective. Only one destroyer received a hit during the landing.
At Bergen, the defensive fortifications put up stiffer resistance to Gruppe 3's approach and the light cruiser Königsberg and the artillery training ship Bremse were damaged, the former seriously. The lack of working lights reduced the effectiveness of the guns though, and the landing ships were able to dock without much opposition. The fortifications were surrendered soon after, when Luftwaffe units arrived. The fortifications at Kristiansand put up an even more resolute fight, twice repulsing the landing and damaging Karlsruhe, nearly causing her to run aground. Confusion soon sprung up though, when the Norwegians received the order not to fire on British and French ships and the Germans began to use Norwegian codes that they had captured at Horten. The Germans also used this opportunity to quickly reach the harbour and unload their troops, capturing the town by 11:00. While most of Gruppe 4 was engaged at Kristiansand, the torpedo boat Greif captured Arendal without any opposition. The main objective at Arendal was the undersea telegraph cable to the United Kingdom. Gruppe 5 encountered the most serious resistance at the inner defensive fortifications of the Oslofjord, in the vicinity of Drøbak. Blücher, leading the group, approached the forts assuming that they would be taken by surprise and not respond in time, as had been the case with those in the outer fjord. It was not until the cruiser was at point-blank range that Oscarsborg Fortress opened fire, hitting with every shell. Within a matter of minutes, Blücher was crippled and burning heavily. The damaged cruiser was sunk by a salvo of antiquated, 40-year-old torpedoes launched from land-based torpedo tubes. She carried much of the administrative personnel intended both for the occupation of Norway and also for the headquarters of the army division assigned to seize Oslo. The cruiser Lützow, also damaged in the attack and believing Blücher had entered a minefield, withdrew with Gruppe 5, 19 km (12 mi) south to Sonsbukten where she unloaded her troops. This distance delayed the arrival of the main German invasion force for Oslo by over 24 hours, though the Norwegian capital would still be captured less than 12 hours after the loss of Blücher by troops flown into Fornebu Airport near the city.
The delay induced by the Norwegian forces gave time for the royal family, Parliament, and with them the national treasury, to flee the capital and continue the fighting against the invasion force. Fornebu Airport was originally supposed to be secured by paratroops an hour before the first troops were flown in, but the initial force became lost in the fog and did not arrive. Regardless, the airfield was not heavily defended and the German soldiers who did arrive captured it promptly. The Norwegian Army Air Service's Jagevingen fighter flight based at Fornebu Airport resisted with their Gloster Gladiator biplane fighters until ammunition ran out and then flew off to whatever secondary airfields were available. The ground personnel of the Fighter Wing soon ran out of ammunition for their anti-aircraft machine guns as well; in the general confusion and focus on readying the fighters for action, no one had the presence of mind or the time to issue small-arms ammunition for the personal weapons of the ground personnel. Resistance at Fornebu Airport came to an end, with the Germans' only loss being a single Junkers Ju 52. Norwegian attempts to mount a counter-attack were half-hearted and effectively came to nothing. On learning of this, Oslo was declared an open city and soon fully surrendered. For Gruppe 6 at Egersund and the paratroops at Stavanger, there was no significant opposition and they quickly captured their objectives.
Battle of Midtskogen
This battle, although very small, had saved the Norwegian royal family. As the invasion had begun, the Norwegian Government fled to nearby Hamar. Among them, a group of Norwegian Royal Guardsmen and some soldiers, possibly from the 5th Regiment in nearby Elverum took positions in Midtskogen to try to stop or slow down the Germans so that the Norwegian royal family could evacuate. In the morning of 10 April, a firefight ended with the retreat of both sides as Captain Spiller, the leader of the German Fallschirmjager, had been hit. Casualties are estimated to five Germans killed and an unknown number wounded, and three Norwegians hit.
Conquest of Denmark
The German plans for the invasion and occupation of Norway relied heavily on air power. To secure the Skagerrak strait between Norway and Denmark, the air bases in Denmark had to be seized. The domination of this strait would prevent the Royal Navy from interfering with the main supply lines of the invasion forces. In this respect, the occupation of Denmark was considered to be vital. The capture of Aalborg Airport was considered particularly important in this respect. The German Wehrmacht crossed the Danish border around 05:15 on 9 April. In a coordinated operation, German troops disembarked at the docks of Langelinie in the Danish capital, Copenhagen, and began occupying the city. German paratroops also captured Aalborg Airport. Simultaneously, an ultimatum was presented by the German ambassador to King Christian X. The Danish army was small, ill-prepared and used obsolete equipment, but resisted in several parts of the country; most importantly, the Royal Guards located at Amalienborg Palace in Copenhagen, and forces in the vicinity of Haderslev in South Jutland. By 06:00, the small Danish Air Force had been taken out and 28 German Heinkel He 111 bombers were threatening to drop their bombs over Copenhagen. King Christian, having consulted with Prime Minister Thorvald Stauning, Foreign Minister P. Munch and the commanders of the army and the navy, decided to capitulate, believing that further resistance would only result in a useless loss of Danish lives. By 08:43 Denmark had capitulated. The Danish public was taken completely by surprise by the occupation, and was instructed by the government to cooperate with the German authorities. Germany's occupation of Denmark lasted until 5 May 1945. An important part of the Danish merchant marine escaped the occupation, as Arnold Peter Møller, President of the Mærsk shipping company, on 8 April instructed his ships on the high seas to move to Allied or neutral ports if at all possible. In a pre-emptive move to prevent a German invasion, British forces occupied the Faroe Islands on 12 April 1940, then a Danish amt (county). The Danish county governor and the Faroese parliament Løgting governed the islands for the duration of the war.
Allied response
Soon after this, the German landings at Trondheim, Bergen, and Stavanger, as well as the skirmishes in the Oslofjord became known. Not willing to disperse too thinly due to the unknown location of the two German battleships, the Home Fleet chose to focus on nearby Bergen and dispatched an attack force. RAF reconnaissance soon reported stronger opposition than anticipated, and this, along with the possibility that the Germans might be controlling the shore defences, caused them to recall the force and instead use the aircraft carrier HMS Furious to launch torpedo bombers at the enemy ships. The attack never commenced though, as Luftwaffe bombers launched an assault of their own against the Home Fleet first. This attack sank the destroyer HMS Gurkha and then forced the Home Fleet to withdraw north when their anti-aircraft measures proved ineffective. This German air superiority in the area led the British to decide that all southern regions had to be left to submarines and the RAF, while surface vessels would concentrate on the north. In addition to the German landings in south and central Norway, the Admiralty was also informed via press reports that a single German destroyer was in Narvik. In response to this, they ordered the 2nd Destroyer Flotilla, mostly consisting of ships previously serving as escort destroyers for Operation Wilfred, to engage. This flotilla, under the command of Captain Bernard Warburton-Lee, had already detached from Renown during her pursuit of Scharnhorst and Gneisenau, being ordered to guard the entrance to the Vestfjord. At 16:00 on 9 April, the flotilla sent an officer ashore in Tranøy Municipality, about 80 km (50 mi) west of Narvik and learned from the locals that the German force was 4–6 destroyers and a submarine. Warburton-Lee sent these findings back to the Admiralty, concluding with his intention to attack the next day at "dawn, high water", which would give him the element of surprise and protection against any mines. This decision was approved by the Admiralty in a telegram that night.
==== First Battle of Narvik ==== Though ten German destroyers had originally taken Narvik, only five remained in the harbour, with three others moving North and the remaining two going west. Early the following morning, Warburton-Lee led his flagship, HMS Hardy, and four other destroyers into the Ofotfjord. At 04:30, he arrived at Narvik harbour and entered along with HMS Hunter and HMS Havock, leaving HMS Hotspur and HMS Hostile to guard the entrance and watch the shore batteries. The fog and snow were extremely heavy, allowing Warburton-Lee's force to approach undetected. When they arrived at the harbour itself they found five German destroyers and opened fire, starting the First Battle of Narvik. Warburton-Lee's ships made three passes on the enemy ships, being joined after the first by Hotspur and Hostile, and sank two of the destroyers, disabled one more, and sank six tankers and supply ships. The German commander, Commodore Friedrich Bonte, lost his life when his flagship Z21 Wilhelm Heidkamp was sunk. However, Captain Warburton-Lee would make a fatal error when he decided to attack the German destroyers one last time. The German destroyers from the North and West converged on the British Fleet at 06:00, while the British were preparing for the final attack. Hardy was severely damaged and beached, and Warburton-Lee was killed. Hunter and Hotspur were both critically damaged, and Hotspur ran into the sinking Hunter. Hostile and Havock meanwhile had raced ahead, but turned about and came back to aid the retreat of Hotspur. The German destroyers were low on fuel and ammunition, allowing Hostile and Havock to come back to aid the retreat of Hotspur.
==== Second Battle of Narvik ==== Shortly after the First Battle of Narvik, two more German ships were sunk by British forces. During the night of 9/10 April, the submarine HMS Truant intercepted and sank the light cruiser Karlsruhe shortly after she had left Kristiansand. On 10 April, the Fleet Air Arm made a long-range attack from their base at RNAS Hatston (also called HMS Sparrowhawk) in the Orkney Islands against German warships in Bergen harbour. The attack sank the disabled German light cruiser Königsberg.
On 10 April, Furious and the battleship HMS Warspite joined the Home Fleet, and another air attack was made against Trondheim hoping to sink Admiral Hipper. Admiral Hipper, however, had already managed to escape through the watch set up outside the port and was on her way back to Germany when the attack was launched; none of the remaining German destroyers or support ships were hit in the assault. In contrast, in the south HMS Spearfish severely damaged the German heavy cruiser Lützow at midnight on 11 April, putting Lützow out of commission for a year. With it becoming more evident that the German fleet had slipped out of Norwegian waters, the Home Fleet continued north to Narvik in the hope of catching the remaining destroyers. En route the ships suffered further harassment from German bombers, forcing them to divert to the west away from the shoreline. By 12 April, they were in range of Narvik and an aerial attack on Narvik from Furious was attempted, but the results were disappointing. It was instead decided to send in the battleship Warspite and a powerful escort force, to be commanded by Whitworth. On the morning of 13 April, Whitworth's force entered the Vestfjord using Warspite's Swordfish floatplane to guide the way. Aside from locating two of the German destroyers, the scouting aircraft also sank the U-64, the first submarine kill by an aircraft. Warspite's destroyers travelled 5 km (3.1 mi) in advance of the battleship and were the first to engage their German counterparts which had come to meet them, thus starting the Second Battle of Narvik. Though neither side inflicted notable damage, the German ships were running low on ammunition and were gradually pushed back to the harbour. By that afternoon, most attempted to flee up the Rombaksfjord, the only exception being Z19 Hermann Künne which beached herself as she made for the Herjangsfjord and was destroyed by HMS Eskimo. Four British destroyers continued to chase the German ships up through the Rombaksfjord, Eskimo was soon damaged by the waiting opposition. However, the German situation was hopeless, having run out of fuel and ammunition, and by the time the remaining British ships arrived, the German crews had abandoned and scuttled their ships. By 18:30 the British ships were making their way out of the now cleared fjord.
Norwegian situation
The German invasions for the most part achieved their goal of simultaneous assault and caught the Norwegian forces off guard, a situation not aided by the Norwegian government's order for only a partial mobilization. Not all was lost for the Allies though, as the repulsion of the German Gruppe 5 in the Oslofjord gave a few additional hours of time which the Norwegians used to evacuate the royal family and the Norwegian Government to Hamar. With the government now fugitive, Vidkun Quisling used the opportunity to take control of a radio broadcasting station and announce a coup, with himself as the new Prime Minister of Norway. Quisling's coup and his list of new ministers was announced at 19:32. The Quisling coup government remained in place until 15 April, when the Administrative Council was appointed by the Supreme Court of Norway to deal with the civilian administration of the occupied areas of Norway, and Quisling resigned. In the evening of 9 April, the Norwegian Government moved to Elverum, believing Hamar to be insecure. All German demands were rejected and the Elverum Authorization was passed by the members of the parliament, giving the cabinet wide-ranging powers to make decisions until the next time the Parliament could be assembled under ordinary circumstances. However, the bleakness of the situation prompted them to agree to continued negotiations with the Germans, set for the following day. As a precaution Colonel Otto Ruge, Inspector General of the Norwegian Infantry, set up a roadblock about 110 km (68 mi) north of Oslo, at Midtskogen. The Norwegian position was soon attacked by a small detachment of German troops, led by Eberhard Spiller, the air attaché for the German Embassy, who were racing north in an attempt to capture King Haakon VII. A skirmish broke out and the Germans turned back after Spiller was mortally wounded. On 10 April, the final negotiations between the Norwegians and Germans failed after the Norwegian delegates, led by Haakon VII, refused to accept the German demand for recognition of Quisling's new government. The same day, panic broke out in German-occupied Oslo, following rumours of incoming British bombers. In what has since been known as "the panic day" the city's population fled to the surrounding countryside, not returning until late the same evening or the next day. Similar rumours led to mass panic in Egersund and other occupied coastal cities. The origins of the rumours have never been uncovered. On 11 April, the day after the German-Norwegian negotiations had broken down, 19 German bombers attacked Elverum. The two-hour bombing raid left the town centre in ruins and 41 people dead. The same day 11 Luftwaffe bombers also attacked the town of Nybergsund, in an attempt at killing the Norwegian King, Crown Prince Olav and cabinet. One of the final acts of the Norwegian authorities before dispersement was the promotion on 10 April of Otto Ruge to the rank of major general and appointment to Commanding General of the Norwegian Army, responsible for overseeing the resistance to the German invasion. Ruge replaced the 65-year-old General Kristian Laake as Commanding General, the latter having been heavily criticized for what was considered to be passive behaviour during the initial hours of the invasion. Elements in the Norwegian cabinet considered General Laake to be a defeatist. Following the appointment of Ruge the Norwegian attitude became clear, with orders to stop the German advance being issued. With the Germans in control of the largest cities, ports and airfields, as well as most of the arms depots and communication networks, repulsing them outright would be impossible. Ruge instead decided that his only chance lay in playing for time, stalling the Germans until reinforcements from the United Kingdom and France could arrive. On 11 April, after receiving reinforcements in Oslo, General Falkenhorst's offensive began; its goal was to link up Germany's scattered forces before the Norwegians could effectively mobilize or any major Allied intervention could take place. His first task was to secure the Oslofjord area, then to use the 196th and 163rd Infantry Divisions to establish contact with the forces at Trondheim.
Ground campaign
When the nature of the German invasion became apparent to the British military, it began to make preparations for a counter-attack. Dissension among the various branches was strong though, as the British Army, after conferring with Otto Ruge, wanted to assault Trondheim in Central Norway while Churchill insisted on reclaiming Narvik. It was decided to send troops to both locations as a compromise. Admiral Lord Cork was in overall command of the Allied operations.
=== Campaign in eastern Norway === After the appointment of Ruge as Commanding General on 10 April, the Norwegian strategy was to fight delaying actions against the Germans advancing northwards from Oslo to link up with the invasion forces at Trondheim. The main aim of the Norwegian effort in eastern Norway was to give the Allies enough time to recapture Trondheim, and start a counter-offensive against the German main force in the Oslo area. The region surrounding the Oslofjord was defended by the 1st Division, commanded by Major General Carl Johan Erichsen. The rest of the region was covered by the 2nd Division, commanded by Major General Jacob Hvinden Haug. Having been prevented from mobilizing in an orderly fashion by the German invasion, improvised Norwegian units were sent into action against the Germans. Several of the units facing the German advance were led by officers especially selected by Ruge to replace commanders who had failed to show sufficient initiative and aggression in the early days of the campaign. The German offensive aimed at linking up their forces in Oslo and Trondheim began on 14 April, with an advance north from Oslo towards the Gudbrandsdalen and Østerdalen valleys. Hønefoss was the first town to fall to the advancing German forces. North of Hønefoss the Germans began meeting Norwegian resistance, first delaying actions and later units fighting organized defensive actions. During intense fighting with heavy casualties on both sides, troops of the Norwegian Infantry Regiment 6 blunted the German advance at the village of Haugsbygd on 15 April. The Germans only broke through the Norwegian lines at Haugsbygd the next day after employing panzers for the first time in Norway. Lacking anti-tank weapons, the Norwegian troops could not hold back the German attack.
