Hitler’s Pre-Emptive War: The Battle for Norway, 1940

by Henrik O. Lunde

  However, the first report about major German naval movements on April 8 came from the Swedish Defense Staff at 1000 hours. The report read “German naval forces consisting of the battleship Gneisenau, the heavy cruiser Blücher and the light cruiser Emden have, accompanied by numerous smaller vessels, passed through the Great Belt during the morning on a northerly course. Destination unknown.”

  The Norwegians called their contact at the Danish Naval Ministry for confirmation and further information. They received a quick reply at 1043 hours:

  Forty-six German räumboote [small minesweepers] and 38 armed trawlers have, according to a report from Østre Flakk Lightship, spread out in northern Kattegat but have not yet passed Skagen [the northernmost point on the Jutland Peninsula]. Gneisenau, Leipzig and Emden passed Langeland between 0600 and 0700 hours on a northerly course, followed by three torpedo boats and six armed trawlers.

  Both the German and British Naval Attachés visited the Norwegian Naval Staff in the course of the morning of April 8. Lieutenant Commander Schreiber, the German Naval Attaché, was the first visitor to Captain Steen, chief of the naval intelligence division. Steen asked Schreiber if the German Ambassador had protested the British breach of Norwegian neutrality (that had occurred when the British laid mines that morning) to the Norwegian Foreign Office. Commander Schreiber answered that this had not been done and he did not think a protest would be made. When Schreiber left, he told Steen, “Goodbye Captain, thank you for the enjoyable time we have spent together.” Captain Steen was a little surprised at this statement and asked if Schreiber was leaving. The German answered no, but that he still wanted to say goodbye.

  A short time thereafter, Admiral Boyes, the British Naval Attaché, arrived. His visit was to have a serious effect on Norwegian expectations and preparations. Boyes asked Steen to report to Admiral Diesen that he had reason to believe that a British fleet was on its way to meet the German naval forces that were reported at sea. Captain Steen assumed that the admiral was speaking about the German naval units in the Kattegat and Skagerrak, but the British in fact had no intention of meeting those units. Instead, Boyes may have meant the German naval forces that the British had sighted on a northerly course in the North Sea the previous day (see later in this chapter). The Norwegian Naval Staff did not know about this sighting.

  The information provided by Admiral Boyes led Admiral Diesen and his staff to conclude that they could expect a major collision between German and British naval forces within a short time and they expected the Germans to be driven back with heavy losses. Admiral Diesen passed this information on to the 1st Naval District.

  New information from the Swedish Defense Staff, received around noon, confirmed the earlier reports about strong German naval units heading north. The Swedes also reported that infantry and artillery units were observed near Rendsburg, heading north towards the Danish border. The Swedes intended to conduct aerial reconnaissance over the Kattegat and report the results to the Norwegians but no further reports were received.

  There were several incidents during April 8 which, taken together with the flow of intelligence reports of German naval and troop movements, should have energized the Norwegians to take immediate precautions. The first incident was the sinking of the German transport Rio de Janeiro in international waters off the southern coast of Norway by the Polish submarine Orzel. This happened at 1115 hours. Rio de Janeiro was one of the 15 merchant ships in the 1st Sea Transport Echelon that had departed German ports on April 4. This ship was carrying troops and equipment destined for Bergen. It was exactly the type of incident the SKL had feared would negate the element of surprise and the reason they had so strenuously opposed the early sailing of the ships in the 1st Sea Transport Echelon.

  The destroyer Odin, the patrol ship Lyngdal, and Norwegian fishing vessels brought about 100 survivors from the sinking ship into Kristiansand and other harbors during the day. These turned out to be uniformed soldiers and naval personnel who reported they were on their way to Bergen to help the Norwegians in accordance with a request from the Norwegians.

  The second incident was the sinking of Posidonia at 1330 hours in international waters at the mouth of Oslofjord by the British submarine Trident. Posidonia was not part of the German operation. However, a small tanker, Stedingen, scheduled to bring fuel to Stavanger also fell victim to Trident on the same day. Finally, a British submarine intercepted Kreta of the 1st Sea Transport Echelon and it sought refuge in Norwegian territorial waters. Kreta, on its way to Kristiansand, was hailed by a Norwegian patrol boat but allowed to proceed. Kreta arrived in Kristiansand on April 13, four days late.

  The Norwegian Naval Staff received two messages during the afternoon from their contact person in the Danish Navy. They received the first message at 1535 hours: “Two ships of the Gneisenau class, one of the Deutschland class, one of the Emden class and three torpedo boats of the Möwe class passed Anholt at 1205 on a northerly course and two auxiliary or mining ships painted a gray color passed Korsør at 1500 on a northerly course.” The second message at 1820 hours read:

  A division consisting of Gneisenau, Deutschland [Deutschland had been renamed Lützow but was still referred to in intelligence reports by its former name], Emden and three torpedo boats of the Möwe class passed Hirtsholm at 1715 hours on a northerly course. Two armed 6,000-ton merchant ships passed through Storebelt on a northerly course. Many people observed on board, possibly troops. Seventeen trawlers also passed that location.

  Twenty minutes earlier, a telegram from the British Admiralty via the Norwegian Embassy in London arrived at the Norwegian naval headquarters:

  German naval forces were observed in the North Sea traveling in the company of what is believed to be a merchant ship, possibly troop transport. Their leading elements were observed this morning outside the Norwegian coast on a northerly course. It is assumed for certain that the goal is to undertake operations against Narvik and they could arrive there before midnight. Admiral Phillips [vice chief of the British Naval Staff] added that the Germans could be in Narvik at 10 P.M. today.

  This was the only warning message the British sent the Norwegians on April 8. Faced with all these alarming reports and incidents, why did the Norwegians not take immediate precautions to meet an obvious threat? While there were divided views about the purpose of the German naval movements, the consensus was that these activities had nothing to do with an attack on Norway. Such an eventuality was ruled unrealistic in view of the Allies’ estimation of German capabilities and overwhelming British superiority at sea.

  A final intelligence report from Denmark seemed to support this conclusion. At 2311 hours the Danes reported that three large warships were observed at 1900 hours, 12 nautical miles north of Skagen Lightship (the northern point of the Jutland Peninsula) on a westerly course at high speed. They stated that these were the same three ships reported on earlier in the day. The westerly course of the German ships appeared to confirm the view held by Admiral Diesen and his chief of staff that the destination was not Norway and they appear to have persisted in their view despite the warning from the British five hours earlier. There were many who viewed the British warning as an attempt to distract the Norwegians from dealing with the British minefields.

  Admiral Diesen refused to believe the statements by the German survivors from Rio de Janeiro that they were headed for Bergen. He believed their statements camouflaged a German operation against a more westerly target, possibly the Shetland Islands or the Faeroes. It is difficult to see how he arrived at this conclusion since he also believed that a German attack against Norway was improbable due to British naval superiority. If he ruled out German operations against Norway because of British naval strength, it seems surprising that he then ruled in operations by the Germans in Britain’s backyard. Furthermore, the naval staff apparently did not find it strange that the reports included a large number of smaller ships (small minesweepers, trawlers, and torpedo boats) unsuitable for distant operations. If these wer
e destined for the Netherlands, they would surely have used the Kiel Canal rather than the long, circuitous, and exposed route around the Jutland Peninsula.

  However, most government officials and members of the Norwegian parliament shared Diesen’s view that the German naval activity did not have Norway as a target and that the Germans would wait to see what the Norwegians did about the British mining before taking any actions. This was a big mistake on the part of the Norwegian military leaders. They failed to appreciate that air power had significantly changed the old concept of naval superiority. Furthermore, they violated an important principle by basing their plans and actions on what they perceived the German intentions to be. It would have been more prudent to base their plans and preparations on German capabilities and the German course of action most dangerous to Norwegian interests. Finally, British actions over the last 24 hours had already given the Norwegians ample reasons to make plans and preparations necessary to defend the country.

  Instead, only minor precautionary measures were taken. At 1820 hours, Admiral Diesen ordered the 1st Naval District to call up additional personnel for the forts. A request for two infantry companies to protect the Bergen and Trondheim forts was passed to the army at 2215 hours but it could not be acted on in time. On recommendations from the commanders of the 1st and 2nd Naval Districts, Diesen ordered the lighthouses from the Swedish border to the entrance of Bergen extinguished. A statement over the national broadcasting system announced this action at 2218 hours. The lighthouses in the 3rd Naval District (and the rest of the 2nd Naval District) were not included in this order, even though the British had reported that German naval forces could be expected in Narvik before midnight.

  The acting commander of the 3rd Naval District pointed out to Admiral Diesen at 2345 hours that there were 14 German merchant ships in Narvik harbor and asked for instructions in case of a British attack on these ships. Admiral Diesen answered 10 minutes later that a British attack on German shipping in Narvik was to be met with force. Similar messages were not sent to the 1st and 2nd Naval Districts but the fact that such messages were even considered necessary tells much about the irresolute nature of the Norwegian Government and its military officials.

  Diesen did not order his forces to the highest state of alert. The 1st Naval District gave a second-stage alert warning to its forces after it was told by Diesen not to activate the highest state of alert “because it would just scare people.” Some lower echelons misinterpreted the 1st Naval District order and proceeded to the highest state of alert. The 2nd Naval District had already ordered its ships to their assigned war stations after the British mining.9

  Crisis Provoked by the British Mining of Norwegian Waters

  Some of the lethargy of the Norwegian authorities can be explained by the fact that they were already trying to manage another crisis, Allied mining of Norwegian waters. The rapidly unfolding events of April 8 were propelling the country precipitously into a war it wanted to avoid at all costs. These events were so confusing that even those who had concluded that the country would find itself at war within a very short time did not know before midnight on April 8 whether they would be fighting the British or the Germans.

  Information about British mining operations in Norwegian territorial waters reached Norwegian authorities at 0420 hours on April 8. Norwegian naval vessels intercepted the British destroyers in territorial waters off the coast near Molde. No armed clashes took place, despite the Norwegian Foreign Minister’s earlier warning to the British that future violations would be met with force. The British action was different from earlier violations of the country’s neutrality: it was an act of war. Norwegian officers protested the mining and the British destroyers left Norwegian waters before noon after Norwegian assurances that they would assume responsibility for warning merchant traffic. The Norwegians received sketches of the simulated minefield.

  At 0600 hours, the British and French Naval Attachés delivered notes to the duty officer at the Norwegian Naval Staff that Norwegian territorial waters had been mined in three places. Only one minefield was actually laid but the Norwegians did not know this until later.

  The British and French diplomatic representatives in Oslo also delivered simultaneous notes to the Norwegian Foreign Office about the mining operations. Koht called the Prime Minister at 0630 hours and requested an emergency meeting of the cabinet. Prime Minister Nygaardsvold decided to consider the problem first at a Foreign Relations Committee session despite Koht’s protest that this would lead to delay.

  Admiral Diesen and Defense Minister Birger Ljungberg met between 0900 and 1000 hours. Diesen recommended that the minefield in Oslofjord be laid as quickly as possible. This act required defense department approval. Commodore Corneliussen, the Admiralty Chief of Staff, was also present. He noted that the Hague Convention required that the mining by neutrals of their territorial waters had to be announced well beforehand and that it would present risks to merchant traffic since there was an insufficient number of patrol vessels available. Why this had not been recognized as a problem earlier is not explained. While two of the nine patrol boats assigned to the 1st Naval District were undergoing repairs, the district had eight torpedo boats and some of these could have filled the void temporarily. Ljungberg did not make a decision but said he would bring the matter to the attention of the cabinet. Diesen raised the issue again later in the day but he was never given authority to mine the approaches to Oslo.

  A joint meeting of the cabinet and the foreign relations committee of the parliament began at 1000 hours, breaking up at 1130. This was about the time that the Norwegians began receiving reports of German naval units on a northerly course through the Great Belt and Kattegat. However, it appears that these events were not discussed. The focus was on what to do about the British mining operations. A decision was made to lodge strong protests against the Allied action and to clear the minefields. Diesen was ordered to prepare to sweep the mines. It was obvious to those present at this meeting that such action could draw Norway into the war, since clearing the minefields would probably lead to clashes with British forces; but if the steps announced were not taken the Germans would have good grounds to take strong measures. The underlying tone at this and subsequent meetings of the Norwegian Government on April 8 was that whatever happened, war with Great Britain was to be avoided. The instructions for clearing the minefields cautioned that force should not be used against overwhelming odds and that the navy should not engage in armed conflict with British destroyers near the minefields except in self-defense.

  The Norwegian protest to the British and French governments was approved at a cabinet meeting that began immediately after the joint meeting of the cabinet and foreign relations committee broke up. The protests were sent to all Norwegian overseas embassies and released to the press at 1255 hours. The Parliament met in open session from 1715 to 1735 hours to hear a report by Foreign Minister Koht. He stated that the Allies were apparently trying to expand the war to Norway and reported on the protests that had been made. The parliament expressed unanimous support for the actions.

  A closed meeting of the parliament started at 1800 hours and lasted until 1915. The Commander-in-Chief of the Navy, the Commanding General of the Army, and their respective chiefs of staff were present. There was a discussion about what do if the neutrality policy failed and Norway was forced to enter the war. This meeting also reached consensus that the Norwegian Government should seek to avoid being drawn into a war against the British. The results of the various meetings appear to give some authority to the conclusions reached by the various political and military leaders in Germany that the Norwegian Government was not willing to enforce its neutrality and that it would probably not offer any meaningful resistance to Allied attempts to occupy strategic points on the Norwegian coast. However, it should be borne in mind that occupation was a very different matter to the mining of waters, and it is possible that the Norwegian Government’s reaction to such an invasion would have been mor
e forceful.

  Warnings Received by the British

  Operations Wilfred (the Allied mining of territorial waters) and R4 (the occupation of designated cities) were originally scheduled to begin April 5 but were postponed to April 8.

  Part of the mining operation was carried out, so what of Allied plans to occupy portions of Norway? To answer this question we must go back and look at the intelligence received by the Allies about German movements, and the consequent decisions that were taken.

  The British received many reports about concentrations of German forces in Baltic and North Sea ports. They also knew that a German intelligence collection ship, Vidar, was positioned off the Norwegian coast. The British decided to leave the ship alone in the hope of breaking the German radio code. As in the case of the Norwegians, the British did not properly piece together the various items of information arriving at the Foreign Office and the three services. This failure properly to coordinate, correlate and interpret the various warnings was a major blunder.

  On March 26, the British Ambassador in Stockholm reported that the Germans had concentrated air forces and naval shipping in Baltic harbors and that their plans might involve the occupation of Norwegian air bases and ports. This was followed by a report by Admiral Darlan that the Germans had assembled shipping for an expedition against ports in southern Norway and Sweden. The Swedish military attaché in Finland, Curt Kempff, had a discussion with his German colleague on April 2 about the German activities in the Baltic. The German assured him that he had no knowledge about German plans in the Baltic and that all the activity had to do with Norway.10 A report of this conversation was forwarded to Stockholm and the Swedes provided the information to the British.

  On April 3, the British War Office received a report that there was a large buildup of German troops near Rostock and that 200,000 tons of shipping had assembled in Stettin and Swinemünde with troops on board. Their alleged purpose was the invasion of Scandinavia. The British concluded that the Germans had taken these steps in order “to deliver a counter-stroke against a possible attack by us upon Narvik or other Norwegian ports,”11 which was precisely the response Churchill was hoping for. Part of the British failure to take these reports as an indication that Germany was preparing to invade Scandinavia can be traced back to the estimate made by the intelligence branch of the British War Office in December 1939, which concluded that 25-30 German divisions would be required for an attack on Norway and Sweden. Intelligence reports about the assembly of a few divisions in northern Germany were discounted since such force levels appeared inadequate for an invasion.