The battle for the iron ore and the access to the Atlantic Ocean

The German invasion of Norway 

Following the invasion of Poland in September 1939, the neutral state of Norway was a key strategic objective for Germany. It was the never-freezing Norwegian port of Narvik through which approximately 80% of the Swedish iron ore could be shipped to Germany year-round. Capturing Norway would also leave Germany with harbors, submarine pens and airfields wherefrom they could strike against Great-Britain. On the other hand, an already planned British occupation (named Plan R 4) of the Atlantic ports of Norway could cut off Germany’s access to the Atlantic. Therefore, exactly 81 years ago, on April 9, 1940 German forces invaded Norway in order to secure the Third Reich’s iron supply and free access to the Atlantic. On the very same day, the Germans launched an attack on Denmark also, which served as a staging area for the larger operation. Six hours after the start of the invasion, after being threatened with the bombing of its capital, Copenhagen, the Danish King and his government capitulated. Taking Norway proved to be a harder nut to crack.

As early as December 1939, plans were starting to form for Norway’s occupation, which were expanded in January 1940, concentrating on the element of surprise and swiftness of execution. Preparations for the invasion, codenamed Operation Weserübung (Unternehmen Weserübung in German), started in March. The invasion was to be presented publicly as the protection of the neutrality of Norway from the Allied forces.

Paradoxically, as Hitler was planning the invasion of Norway, so were the Allies. Plans were drawn up for landings near Narvik, Trondheim, Stavanger and Bergen, ostensibly to deliver troops to Sweden and then to Finland, to aid the Finns locked in combat with the USSR. However, with Finland’s capitulation on March 13, the Winter War ended, thus the pretext of a British landing in Norway was void. Still, on April 8, three days later than planned, the British started mining the coastal waters of the Scandinavian country under Operation Wilfred. The original intent of the operation was to force the ore transports to sail through the North Sea, where the Royal Navy could intercept them but with the events unfolding this got cancelled.

On April 9, the German fleet deployed General Nikolaus von Falkenhorst’s landing force. The ground forces were assembled in the XXI Army Corps, including the 3^rd Mountain Division and five infantry divisions. Three divisions would start the assault, with the remainder to follow in the next wave. Three companies of paratroopers would seize airfields. The 2^nd Mountain Division was involved later. The key locations were to be occupied by six groups (Gruppe 1, 2, 3, etc.) via amphibious landings supported by paratroopers. Most of the German submarines of the region also supported the invasion in Operation Hartmut. Within a short time, the five most important Norwegian harbors, including Narvik, were in German hands. The airports of Oslo and Stavanger were taken by paratroopers while Luftwaffe bombers dominated the air. German troops rapidly advanced inland, meeting little resistance. The Norwegian forces were taken by surprise, their situation was not aided by the Norwegian government's chaotic mobilization orders either. On April 10, the 65-year-old Commanding General of the Royal Norwegian Armed Forces, General Kristian Laake was replaced by Colonel Otto Ruge. Laake was heavily criticized for his passive behavior during the initial hours of the invasion. He realized that the Germans have to be stalled until the British and French reinforcements arrive.

In the early morning of April 9, Group 5 (Gruppe 5) encountered the most serious resistance at the inner defensive fortifications of the Oslofjord, at the Drøbak Strait. Its mission was to capture the Norwegian capital, and it was hoped that in the surprise operation they could capture the government and the royal family which would eventually lead to a Norwegian capitulation and a peaceful occupation of the country. Group 5 consisted of the two heavy cruisers Blücher, and Lützow, the light cruiser Emden, the torpedo boat Möwe, and other smaller vessels like minesweepers. Blücher, leading the group, approached the fortress of Oscarsborg assuming that they would be taken by surprise and not respond in time, as had been the case with those in the outer fjord. No one could have expected Oscarsborg to put up any significant resistance: it was built in the early 19^th century, and two of its main guns were 48-year-old German-made Krupp guns (nicknamed Moses and Aron) of 280 mm (11 inches) caliber. On top of that, all personnel except officers and NCOs were freshly conscripted recruits – in fact, even the fortress’ minefield was undeployed, as deploying it was to be part of a training exercise a few days later. The fort had one single weapon that the German military intelligence was unaware of: an underground torpedo battery, put into service in 1901, designed to fire a salvo of six torpedoes at hostile ships sailing past the fort. The battery used 40-year-old, obsolete Whitehead torpedoes. The fortress was commanded by 64-year-old Colonel Birger Eriksen, and the torpedo battery was supervised by Commander Senior Grade Andreas Anderssen, himself already retired and called back by Colonel Eriksen to stand in for an officer away on sick leave. Thus, it was a crew of pensioners and untrained conscripts with outdated weaponry who stood against the freshly commissioned Blücher and the rest of Group 5.

It was not until Blücher was at point blank range that Oscarsborg Fortress opened fire, hitting with every shell. One round penetrated the Blücher’s armor and exploded inside a magazine holding oil, bombs and depth charges, starting an intense fire. The second shell knocked out electricity in the cruiser’s main guns, disabling them. Within a matter of minutes, Blücher was crippled and burning heavily. The damaged cruiser was sunk by a salvo of the antiquated torpedoes. Within two hours, the badly damaged ship, unable to maneuver in the narrow fjord from multiple hits, sank with heavy casualties totaling 600–1,000 men.  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. Many of the 2,000 sailors and soldiers swimming for their lives in the freezing water were covered by oil seeping from the wreckage and burned to death when it caught fire.

The cruiser Lützow, also damaged in the attack and believing Blücher had entered a minefield, withdrew with Group 5, 19 km (12 miles) 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 paratroopers flown into Fornebu Airport near the city. Over the course of the dawning day the fort was heavily bombarded by the Luftwaffe and, cut off from support, Colonel Eriksen surrendered the next morning. The threat from the fortress (and the mistaken belief that mines had contributed to the sinking) delayed the rest of the naval invasion group long enough for the royal family, the cabinet and parliament to be evacuated, along with the national treasury.

The main German thrust advanced northward from Oslo towards Trondheim in the center of the country. It took almost a week for the Allies to mount a counteroffensive and land troops on the western shores of Norway. Due to the problems in command, eventually Admiral Lord Cork was given overall command of the Allied operations on April 21. The hastily deployed French and British forces failed to take Trondheim and the beleaguered troops had to be evacuated in early May. The Norwegian commander, Otto Rugge was furious and said that with the evacuation Norway was to share the fate of Czechoslovakia and Poland. By May 5, the last pockets of Norwegian resistance in the area surrendered, and the south of the country was firmly in German hands.

In Northern Norway a major battle unfolded around the port of Narvik both on land and at sea and not in the favor of the Germans. On May 27, the British and French troops together with the Norwegian 6^th Division and the Polish Independent Highland Brigade took Narvik from the outnumbered German 3^rd Mountain Division and surviving sailors from their sunken destroyers pushing them almost to the Norwegian-Swedish border behind their back to the east. This was the first occasion that a city was retaken from the German forces in WWII. Still, the victory was short-lived; the unfolding Battle of France forced the Allies to evacuate their troops from Norway under Operation Alphabet (for instance, British expeditionary forces were already being evacuated from France via Dunkerque). On June 10, after 62 days of resistance, the last Norwegian troops capitulated. The formal capitulation agreement was signed at the Britannia Hotel in Trondheim.

In the campaign, the Germans suffered 5,296 casualties. Of these, 1,317 were killed on land, 2,375 lost at sea, and 1,604 were listed as wounded. The German navy, the Kriegsmarine, paid a very high cost for this operation and this was the last occasion that they delivered a large-scale amphibious operation. The Norwegian and Allied losses totaled around 6,602. The British lost 1,869 killed, wounded and missing on land and approximately 2,500 lost at sea, while the French and Polish lost 533 killed, wounded and missing. On the Norwegian side there were around 1,700 casualties, of whom 860 were killed. Some 400 Norwegian civilians were also killed. The Allies lost masses of equipment during the repeated evacuations.

King Haakon VII, having stalwartly refused the Nazi’s requests to appoint Vidkun Quisling, the pro-Nazi former defence minister and the leader of Norway's fascist party (Nasjonal Samling - "National Gathering" in English), as head of a pro-Nazi government. King Haakon, Crown Prince Olav, and the Cabinet Nygaardsvold left from Tromsø on June 7 aboard the British cruiser HMS Devonshire to establish a Norwegian government-in-exile in London. The occupied country was governed by the Reichskommissariat Norwegen and Quisling’s puppet government (the latter’s name became a synonym for “traitor”). Hitler had free access to both the waters of the North Atlantic and Swedish iron ore. Norway remained under German occupation until the end of the war. During the occupation, a resistance movement named Milorg started to unfold which became more and more efficient against the occupants with support coming from the government-in-exile. One of their most successful operations was sabotaging the Norwegian heavy water production, which crippled the German nuclear weapon project through a series of commando and bombing raids.