Operation Weserübung

• 1. Introduction

  ›

  Operation Weserübung began at 05:15 on the morning of the 9th of April 1940, when German forces struck Denmark and Norway in one of the most daring and unconventional military gambits of the entire war. Within a single day, port cities stretching from Kristiansand in the south to Narvik deep inside the Arctic Circle had fallen. Within six hours, an entire nation had surrendered. The questions that follow are harder than the military timetable: why did Germany need Scandinavia at all, how did a plan dismissed as reckless by much of the Wehrmacht get approved, and what made Norway's resistance so unexpectedly consequential despite the speed of the German advance? The answers reach from Swedish iron ore fields to a fortress guarding a narrow fjord, from a Nazi collaborator's radio broadcast to a Norwegian king who refused to sign his country away.

• 2. Iron Ore and the Strategic Calculus

  ›

  German industry was heavily dependent on iron ore imported from mines in Swedish Lapland, and the most efficient route ran through the ice-free Norwegian port of Narvik. By the spring of 1939, the British Admiralty had begun eyeing Scandinavia as a potential theatre of war precisely because of that supply line. Control of the Norwegian coast could tighten a blockade that would choke German industry.

  In October 1939, Grand-Admiral Erich Raeder brought the threat directly to Adolf Hitler. Raeder argued that Allied bases in Norway would be dangerous and that a German occupation of the country would let the Kriegsmarine dominate the nearby seas and use Norway as a launching platform for submarine operations against Allied shipping. The other branches of the Wehrmacht were uninterested, and Hitler's initial directive kept the main focus on a land offensive through the Low Countries.

  Winston Churchill, newly appointed to the Chamberlain war ministry, proposed mining Norwegian waters in an operation called Wilfred. Forcing iron ore transports into the open North Sea would expose them to the Royal Navy. Churchill assumed the mining would provoke a German reaction, triggering the Allied occupation plan known as Plan R 4. Chamberlain and Lord Halifax rejected the idea initially, worried about the reaction of neutral nations including the United States.

  The Winter War between the Soviet Union and Finland, which began in November 1939, reshuffled the strategic picture. Britain and France began planning to send forces through northern Norway and into Sweden under the cover of Finnish aid, with Narvik as the entry point and the Iron Ore Line railway between Narvik and Luleå as the prize. The Moscow Peace Treaty ending the Winter War, signed in March 1940, stripped away the justification for that plan. But the race for Norway was already under way on both sides.

• 3. From Studie Nord to Weserübung

  ›

  Vidkun Quisling's visit to Hitler on the 14th of December set German planning in motion. After that meeting, Hitler ordered the Oberkommando der Wehrmacht to begin preliminary work on a Norwegian invasion. The first outline, called Studie Nord, was a modest concept calling for just one division of German troops.

  Between the 14th and the 19th of January 1940, the Kriegsmarine rebuilt the plan from the ground up around two principles: surprise was essential, and fast warships rather than slow merchant vessels should carry the troops. Simultaneous seizure of all targets depended on speed. The revised plan called for a full army corps: a mountain division, an airborne division, a motorized rifle brigade, and two infantry divisions. Target cities included Oslo, Bergen, Narvik, Tromsø, Trondheim, Kristiansand, and Stavanger. The planners also hoped to capture the kings of both Denmark and Norway quickly enough to force rapid surrenders.

  On the 21st of February 1940, General Nikolaus von Falkenhorst was given command of the ground operation. He had experience from Finland during the First World War and understood Arctic warfare, but his authority extended only to ground forces. The plan was formally named Operation Weserübung on the 27th of January 1940. The ground component would be the XXI Army Corps, built around the 3rd Mountain Division and five infantry divisions, none of which had yet seen combat. Three companies of Fallschirmjager were assigned to seize airfields.

  The Luftwaffe's demand to capture fighter bases and air warning stations drove a crucial addition on the 1st of March, when Hitler issued a new directive requiring the invasion of Denmark as well. The XXXI Corps was formed for that purpose, consisting of two infantry divisions and the 11th motorized brigade. The entire operation would draw on the X Air Corps, with roughly 1,000 aircraft. Almost all U-boat operations in the Atlantic were suspended so that every available submarine could contribute under Operation Hartmut.

• 4. Denmark Falls Before Breakfast

  ›

  At 04:00 on the 9th of April 1940, the German ambassador Cecil von Renthe-Fink telephoned Danish Foreign Minister Peter Munch and asked for a meeting. When the two men sat down twenty minutes later, Renthe-Fink stated flatly that German troops were already moving in to protect Denmark from Anglo-French attack. The demand was simple: Danish resistance must stop immediately. If it did not, the Luftwaffe would bomb Copenhagen.

  German forces had already been moving for several minutes before that conversation ended. Troops had landed at Gedser via a regular commercial ferry at 03:55, moving north. Fallschirmjager units made unopposed landings at two airfields near Aalborg, seized the Storstrøm Bridge, and took the fortress of Masnedø, marking the first recorded paratrooper attack in history.

  At 04:20, a reinforced battalion from the 308th Regiment landed in Copenhagen harbour from a minelayer and rapidly captured the Danish garrison at the Citadel. The Germans then moved on Amalienborg Palace to seize the Danish royal family. The King's Royal Guard had been alerted and reinforcements were arriving, and the first German assault on the palace was repulsed, giving King Christian X and his ministers time to confer with Danish Army chief General Prior. Overhead, Heinkel He 111 and Dornier Do 17 bombers dropped leaflets reading, in Danish, OPROP!, meaning proclamation. At 05:25, two squadrons of Messerschmitt Bf 110s attacked Vaerlose airfield, destroying ten Danish aircraft and seriously damaging fourteen more, wiping out half the Army Air Service.

  With Copenhagen under explicit threat and only General Prior willing to fight on, King Christian and the full Danish government capitulated at approximately 06:00. The invasion had lasted less than six hours, the shortest German military campaign of the war. That rapid capitulation led to an unusually lenient occupation, particularly before the summer of 1943, and to a delay in the arrest of Danish Jews that allowed nearly all of them to be warned and reach neutral Sweden. Of a pre-war Jewish community of just over 8,000, 477 were ultimately deported and 70 lost their lives.

• 5. Norway Fights the Fjord

  ›

  Late in the evening of the 8th of April 1940, the Norwegian guard vessel Pol III spotted German ships approaching the Oslofjord. Her captain, Leif Welding-Olsen, was fired upon and became the first Norwegian killed in the invasion. The German fleet pressed up the fjord toward the Drobak Narrows.

  In the early morning of the 9th of April, gunners at Oscarsborg Fortress picked out the lead ship in their spotlights at around 04:15. Two of the fortress guns were 48-year-old Krupp artillery pieces of 280 mm caliber, nicknamed Moses and Aron. Within two hours the heavy cruiser Blucher, hit repeatedly by artillery and torpedoes and unable to maneuver in the narrow fjord, sank with the loss of between 600 and 1,000 men. That delay, combined with a mistaken belief that mines had contributed to the sinking, gave the Royal Family, the Cabinet, members of Parliament, and the national treasury time to evacuate by special train heading north. Along their route they encountered fighting at Midtskogen and bombing at Elverum and Nybergsund.

  Because the King and the government escaped capture, Norway never legally surrendered to Germany. The Quisling regime, which Vidkun Quisling announced via radio broadcast at 7:30 p.m. on the 9th of April, was illegitimate from the start. The Norwegian government-in-exile in London remained an Allied nation throughout the war.

  At 7:06 p.m. on that same day, five Norwegian fighters were sent up against 70 to 80 German aircraft. German airborne forces landed at Oslo's Fornebu airport, Kristiansand's Kjevik airport, and Sola Air Station, the last of which was the first opposed paratrooper attack in history. Among the Luftwaffe pilots landing at Kjevik was Reinhard Heydrich. Bergen, Stavanger, Egersund, Kristiansand, Arendal, Horten, Trondheim, and Narvik were attacked and occupied within 24 hours.

• 6. Narvik and the Long Retreat

  ›

  Narvik was the geographic heart of the entire operation. Roughly 90% of Swedish iron ore exported through Norway passed through that port, and securing it was Germany's most pressing strategic goal. General Eduard Dietl led 2,000 Gebirgsjager, mountain infantry, in the landing force carried by ten destroyers.

  On the 10th of April, five British destroyers engaged Dietl's naval escort in the First Battle of Narvik. Both sides lost two destroyers. Three days later, on the 13th of April, the British battleship and a flotilla of destroyers returned and sank the remaining eight German destroyers, which had been trapped in harbour because of fuel shortages.

  On land, Norwegian and Allied forces under General Carl Gustav Fleischer achieved the first tactical victory against the Wehrmacht anywhere in the war, driving the Germans out of Narvik on the 28th of May. That success was short-lived. The deteriorating situation on the European continent forced the Allies to withdraw in Operation Alphabet. On the 9th of June, the Germans recaptured Narvik, which civilians had already abandoned because of Luftwaffe bombing.

  King Haakon VII, Crown Prince Olav, and the Cabinet Nygaardsvold left Tromso on the 7th of June aboard a British cruiser to represent Norway in exile. The Norwegian Army on the mainland capitulated on the 10th of June 1940, two months after Wesertag. That made Norway the occupied country that had withstood a German invasion for the longest period before falling. Hegra Fortress in its own battle held out until the 5th of May, and the King returned to Oslo on the same date five years later, the 7th of June 1945.

• 7. The Nuremberg Verdict on Preemption

  ›

  At the Nuremberg trials in 1946, Germany's defense argued that the invasion was compelled by the need to forestall an Allied attack and was therefore preemptive. The defense pointed to Plan R 4 and its predecessors. The International Military Tribunal rejected that argument.

  The tribunal found that Germany had been discussing invasion plans as early as the 3rd of October 1939, when a memo from Admiral Raeder to Alfred Rosenberg addressed the subject of gaining bases in Norway. Raeder had written questions including, "Can bases be gained by military force against Norway's will, if it is impossible to carry this out without fighting?" Two diary entries by Alfred Jodl dated the 13th and the 14th of March 1940 revealed the true state of German decision-making. The first read: "Fuhrer does not give order yet for 'Weser Exercise'. He is still looking for an excuse." The second: "Fuhrer has not yet decided what reason to give for Weser Exercise."

  The Naval Operational Order for Weserubung was not issued until the 4th of April 1940. The British mines that were supposed to provoke a German response were not laid until the morning of the 8th of April. By that point the German invasion fleet was already advancing up the Norwegian coast. The tribunal concluded that no Allied invasion had been imminent, and the preemption argument failed. The Royal Norwegian Navy and other Norwegian forces continued fighting Germans abroad and at home until Germany's final capitulation on the 8th of May 1945.