164: British and French Invasion Plans


The German military would invade Norway in April 1940, but not before the British and French came very close to beating them.



Hello everyone and welcome to History of the Second World War Episode 164 - The Invasion of Norway Part 2 - British and French Invasion Plans. This week a big thank you goes out to Benjamin, Jeffrey, Henk, fakefur, and Bree for choosing to support the podcast by becoming members, you can find out more over at historyofthesecondworldwar.com/members. Germany would be the nation that would invade Norway in April 1940, but only because the British and French got cold feet with their plans to do the same thing. Their reasons were different, instead of the German desire to invade and control the entire country to prevent it from being used by Britain and France while the Allied plan was built around the desire to slow the export of Swedish iron ore to Germany. But for both nations, at the core of their plans was the simple fact: the desires of the Norwegian government and the Norwegian people were secondary. For British and French leaders there was another reason to bring the war to Norway, it would keep it away from France. Many of the discussions that occurred on the British and French Supreme War Council were around how Germany’s attentions could be pulled somewhere, anywhere, to delay an attack into northeastern France. The goal was to take the pain, suffering, death, and destruction that war caused and shift it onto somewhere and someone else, in this case the people of Norway and Sweden, who had no say in the matter. Publicly they would find other reasons for their actions, the stoppage of iron ore, the protection of Norway from possible Russian aggression, but those were never the real reasons for the planned invasion. This episode will discuss these plans, why they were not put into action, and then the state of British and French forces on the eve of the German invasion.

Concrete British plans for some kind of intervention in Norway date back to April 1939 when a report was published by the Admiralty around the importance of Norway to a possible Anglo-German war. This report drew heavily on the writings of the German Admiral Wolfgang Wegener, Wegener had written a book in the late 1920s which discussed how control of Norway was essential to a successful German war against Great Britain . This control would allow the German Navy to break out of its narrow access to the North Sea and instead be able to utilize the entire Norwegian coastline to stage naval vessels, making it far easier to threaten the Royal Navy and British trade. The benefits to the German Navy were obvious, and so was the threat to the Royal Navy if it could be achieved, but before the war the general belief among the Admiralty was that the only way for Germany to invade Norway was through a seaborne invasion, and that would not be possible due to the overall power and strength of the Royal Navy. After the declaration of war the focus of planning shifted from preventing Germany from invading Norway to how to proactively prevent the flow of Swedish Iron Ore to Germany. A key pillar of the British and French war effort in the early months of the conflict was economic war against Germany, and they believed that the Swedish Iron Ore was absolutely essential to the German war effort. They did not have great information about what was happening in the German economy, but British economists estimated that if the flow of Swedish iron ore could be stopped for a year it would cripple Germany’s ability to wage war. They were wrong about this, but that is sort of beside the point. Initial discussions revolved around using diplomatic pressure on Norway to try and get them to stop allowing the iron ore to flow throw Norway and the Norwegian port of Narvik. But as early as September 18th, 1939 Churchill, as First Lord of the Admiralty, would make it clear to his staff that if the diplomatic approach did not yield the proper results, then the next option would be to start violating Norwegian territorial waters to interdict the trade directly. During September, the plan that Churchill favored was the laying of British minefields along the Norwegian coast which would obviously cause problems for merchant ships that were moving between Narvik and Germany. But this very passive approach to trade interdiction was not really Churchill’s style, and so he and others at the Admiralty began to advocate for more action. This would be a common thread among all of Churchill’s war plans, in both World Wars, he was at the head of the group of British leaders that believed that the best way to fight a war was through proactive action against the enemy, even if those actions were small, even if those actions were risky. There would be no immediate action against Norway though, but then in November the Soviet Union invaded Finland, which caused a new series of discussions about what should or should not be done about the overall situation in Scandinavia.

The possibility of a British and French intervention in the conflict between Finland and the Soviet Union was discussed a bit back in the Winter War episodes. But to review just a bit, there were many discussions in late 1939 and early 1940 in London and Paris around what could be done to assist Finland more directly in the conflict. This would almost certainly depend on getting troops to Finland, but there was not an obvious way to do so, or at least to get them to the places they were most needed which was central and southern Finland. For both the initial movement of troops and then supplying those troops it would be far easier if, instead of using a purely nautical supply route through the Arctic Circle, a Norwegian port, probably Narvik was used and then a supply route across Sweden. But this kind of action would need the cooperation of both Norway and Sweden, who were both terrified of the fact that if they were to help the British and French, Germany would immediately invade from the south. It was also of course possible that such actions would cause the Soviet forces to also attack Norway and Sweden, which was also not desirable. In British and French planning the possibility of a war with Russia was understood, but it was not as much of a concern as it probably should have been. It would be too much to say that they did not care about the ability of the Soviet military forces, but the discussions that occurred and the recommended actions that could have brought the Soviet Union into the war on the side of Germany make it very clear that both the French and British leaders drastically underestimated the impact that the Soviets would have on the war if they entered. As Halifax would tell the British ambassador to Turkey in February 1940, the British government “were not disposed to declare war upon Russia, but, at the same time, were not disposed to be deterred from any action that might suggest itself to us for fear that Russia would declare war on us.” The way that they discount Soviet actions flirts with being comical, with possible intervention in Finland not even being the most bizarre scheme that might have resulted in Soviet entry. In the end the only thing that would really prevent any of these plans from happening was general hesitancy on the side of the Allied leaders, and in some ways they were saved from the massive mistake of attacking the Soviet Union only by Germany’s actions in Norway and Western Europe. One of the challenges with providing aid to Finland was that it was difficult to scrape together enough resources to be actually impactful on the events in Finland. And perhaps quite tellingly, the vast majority of the planned troops to be sent to Scandinavia would never actually make it to Finland, with the majority of any troops sent either staying in Norway or Sweden.

That may seem odd, that most of the troops sent to help Finland would never actually be sent to Finland, but it was mostly due to the real reasons that such assistance would be provided, and it all came back to Swedish Iron Ore and trying to pull the Germans away from France. The theory was that if an expeditionary force was sent to Norway and then possibly to Sweden, it did not actually matter whether or not they ever made it to Finland. Such an action, would prompt a German response, which would take some time, and then might delay the attack on France, with any postponement of a possible Spring 1940 attack giving both the French and British more time to prepare and it would give more time for the economic war to have a negative impact on Germany. From the beginning, the theory was that even a small initial force sent to Norway would result in an escalation spiral, with ever greater number of troops being required due to Germany’s commitment of forces. With Churchill writing “As soon as Germany saw that we were laying our hands on the iron ore from Narvik she would take action against southern Scandinavia which would give us full justification for the larger operation.” This was pitched as a benefit of the plan, the more Germany sent to Norway the less they would have for France. The French government and military were huge fans of this plan, and in fact the French Premiere Daladier would directly propose a similar plan in mid-December 1939 at a meeting of the Supreme War Council. The plan that Daladier presented would involve a join British and French expeditionary force landing in Narvik and then moving into Sweden to capture the Swedish port of Luleå. With both of these ports under Allied control the flow of Swedish Iron Ore would be completely halted. This roughly aligned with the plans already being developed by the British military leaders, with serious British planning occurring as early as November 1939 for armed intervention in Norway. The Chief of the British Imperial General Staff Sir Edmund Ironside later recalled, “I was searching for some method by which we could divert the attention of Germany from her offensive strategy against us, which must soon be let loose against France. The first inklings of a possible expedition against Norway came before the Chiefs of Staff Committee in mid-November. It came from the Planners in the form of a project to help Norway if she were attacked by Russia.” Churchill would make his pitch to the British war cabinet in mid-December that it was a good time to enact some of these plans stating “we had everything to gain by the war spreading to those countries [Norway and Sweden] so long as we retained our command of the sea. … It would give us the opportunity to take what we wanted, and this, with our sea power, we could do.” On December 22nd, the decision would be made to not pursue the path of invasion, at least for the time being, and instead to focus on increased diplomatic pressure on Norway and Sweden to try and slow the movement of the iron ore.


In the first week of January 1940 a diplomatic note was handed to the Norwegian Ambassador in London. It used a few recent examples of Greek and British merchant ships which were sunk in Norwegian waters as examples of ways in which Norway was not meeting the expectations placed on neutral nations to prevent the misuse of their territorial waters. From the British perspective this note was written to provide a warning to Norway and to prompt them into greater action against possible German intrusion on their waters. The Norwegian perspective was completely different, and they viewed the note as signaling a threat to their neutrality. One of the common tactics used by beligerent nations during wartime was to take tiny mistakes and accusations and then turn them into massive diplomatic incidents that then turned into an excuse for war. This was a favorite tactic of the Germans, and to the Norwegian government they were concerned that they were now getting the same treatment from the British. But in the immediate aftermath of the diplomatic discussions the Norwegians did not have anything to worry about because the plans for action against the iron ore traffic, either invasion or minelaying, were shelved. The reason that the actions were not pursued were primarily down to the concerns of British leaders that any action around Norway would lead to some kind of disaster. The decision to not pursue the invasion also came on the heels of a report provided to the War Cabinet in early January which stated that if the expeditionary force was going to be successful it needed to be far larger than previously planned. Instead of a few thousand men, the belief of the Chiefs of Staff was that it would require up to 2 entire divisions of troops, a tenfold increase in overall commitment. This was a real possibility, as would be proven in later actions, the British and French militaries were at this stage of the war not organized enough to carry out large complicated plans like would have been required for a large expeditionary force into Scandinavia. The staffing experience simply did not exist, and it would take time for the skills and experience to be developed. The simpler mining plan did not have the upside, and would have destroyed relations with Norway without the benefit of truly halting the movement of Swedish iron ore.

By the end of January all plans for actions that would violate Norwegian neutrality were shelved, only to then magically reappear in late March. Unlike during the earlier discussions, things moved very quickly and over just a few days in late March and then the first few days of April important decisions were made in London and Paris. The two governments would agree to move forward with plans to place mines in Norwegian waters to stop the flow of iron ore traffic. A few days before these mines were put in place the governments of Norway and Sweden would be notified, and they would also be told that the British and French governments were taking this action because they believed they had the right to stop the iron ore from reaching Germany. This note would be sent on April 1st, and the mining would begin on April 5th, although this timeframe would later be delayed so that the note would be delivered on April 5th and the invasion to start on April 8th. Along with this mining operation, the idea of landing troops in Norwegian ports also resurfaced, and was added in to plans with very little discussion. And instead of just Narvik, troops would also be landed at the Norwegian ports of Trondheim, Bergen, and Stavanger with the plans for some of these troops to then move into Sweden. During the earlier rounds of planning and discussion there had been endless conversations about these types of landings, and the commitment of troops had been one of the primary reasons no actions were taken. Then in late March they were thrown into the plan with very little conversation. On the British side the expected German response to these actions was that they might take control of some areas of southern Norway to be used as air and naval bases to hit back against the British and French forces. But at the same time General Ironside recommended that plans be made to withdraw 2 or three divisions from France in case of a larger German response. A larger German response was discussed in a variant of the plans that was called R4, R4 would be activated if the Germans invaded Norway before the British and French arrived. As part of this plan the same basic landings would be made, but their emphasis would be maintaining defenses in the Norwegian ports that they landed in. The only offensive action would be in Narvik with the goal of securing the railway from Narvik to the Swedish border. The initial commitment of troops had also continued to increase, from the early planning of a few battalions by late March the operation had grown to more than 4 entire divisions. This represented a total of 100,000 British and 50,000 French and Polish troops, along with a large naval and air presence. This massive increase in required troops had been part of the continued planning that had occurred among the military staffs during February and March, planning that had continued even after the decisions of December and January not to pursue any immediate action. The growth of the required forces has always been a very common theme in military operations, with a high level plan seeming possible with a small number of troops, but that number grows the more detailed the plan becomes until what was a few thousand turns into 150,000. But what seems evident in all of this planning is that many of the inhibitions of December and January were suddenly gone, even though the overall situation in the war had not drastically changed. Supporters of the operation, like Churchill, largely still supported it for the same reason, with Churchill saying “Once ashore we should have secured a valuable prize not only in the possession of about a million and a half tons of iron ore, but also in our occupation of the harbour which would be of the greatest use for naval purposes. Even if the railway had been sabotaged, our forces should install themselves securely in the port in the hope that ultimately we might persuade the Scandinavians to give us railway facilities for a further advance.” The major difference was that those who had halted earlier efforts were simply more muted in their concerns, and less firm in their resistance to the idea in late March when compared to earlier months, and so without any push against the plan, those pushing for action in Scandinavia would get their wish. Even men like the British Foreign Minister Halifax had been brought around on the idea due to the concerns that if the British and French did not do something soon then the Reynaud government in France would fall.

At 7PM on April 5th another meeting would occur between the British and French embassies in Norway and representatives of the Norwegian government. The reason for the meeting was for the delivery of an official note from both the French and British governments. The note claimed that the Norwegians were under too much pressure from Berlin and were no longer able to act independently, as they should be able to as neutrals. The note went on to say that the governments of Britain and France could no longer tolerate the movement of war critical supplies to Germany from Scandinavia. Then to quote a bit of the note, it was to “notify the Norwegian government frankly of certain vital interests and requirements, which the Allies intend to assert and defend by whatever measures they may think necessary.” The note then laid out five reasons why the British and French felt that they had to take the actions they were about to take, with the fifth being the most important because it was in the fifth point when the British and French governments claimed that they were actually working on behalf of neutral nations like Norway, they were helping! and they just wanted to make sure that Norway was not being taken advantage of by the Germans. The note would close by saying that they believed that they had the right “… to take such measures as they may think necessary to hinder or prevent Germany from obtaining from those countries’ resources or facilities which for the prosecution of the war would be to her advantage or the disadvantage of the Allies… . The shipping of Norway, Sweden and other neutral countries is attacked and destroyed almost daily by German submarines, mines and aircraft, in defiance of international law and with deliberate disregard for the loss of life involved. The Allies will certainly never follow this example of inhumanity and violence, and when the successful prosecution of the war requires them to take special measures, the Norwegian Government will realise why they do so … and the Allied Governments feel confident that this fact will be duly appreciated in Norway.” By claiming that the Norwegian government was under German pressure, the British and French were essentially just saying that they could do whatever they felt was right, without considering the thoughts of the Norwegians. What was not included in the note was any kind of information about what the Allies planned to do or when they planned to do it.

While the note was being prepared for delivery, starting on April 5th various forces of the Royal Navy began to leave their ports to begin their pre-invasion operations. Several different groups of ships would leave Scapa Flow to begin mine laying operations, while the Homefleet was prepared for action. The heavy forces of the Royal Navy were not required for the initial plan, but they would still be prepared to act against any possible German action. What none of the British and French leaders knew was that at the exact same time that they were preparing for action, the Germans were as well. And in fact the Germans had already put into practice their plans for the invasion when various supply ships left German ports on April 3rd. We will catch up on the German plans for their invasion next episode.