Pre war plans and considerations
The strategic importance of the Scandinavian peninsula had been raising ever since the 19th century. One factor was the opening of the vast iron ore fields in northern Sweden. Another was the unification of Germany, leading to the appearance of a new power with geo political ambitions. The ore fields became an important source of high quality iron for the rapidly expanding German industry. Denmark and southern Norway also became potential bases in a conflict between Britain and the new Great Power, Germany.
Map over strategic railways and the ore fields in Scandinavia.
The German navy had plans for expanding its base area by occupying Danish ports already in the 19th century. Later they were expanded to include the occupation and use of Norwegian ports. The main reason was of course the wish to avoid being easily blockaded by the British fleet. On a higher level there were however no plans for going north. A calm situation up in the north was considered more important, in order to secure the import of raw materials.
In the spring of 1939 there was unofficial planning by the British admiralty for mining of Norwegian waters (with or without Norwegian consent). The goal was to get a complete blockade of German shipping and naval movement.
The strategic value of the Swedish export of iron ore to Germany is realized in Britain, and some half-hearted attempts are made to bring it down with diplomatic measures.
The situation in late 1939
After the swift German occupation of Poland in September 1939, the war still to evolve into a real world war, faded down to a lull. Germany was still not ready to fight a decisive battle with the allies (France and Britain), and they were very unwilling to start a new war like the First World War.
After the fall of Poland it was not clear to the German leadership how to pursue the war in the west. As the combined Anglo-French declaration of war was a surprise to Hitler, there was no clear strategic plan ready. In the discussions that followed there were two main directions. Either a decisive land battle in France, or a naval blockade of Britain. The latter would be done with submarines. After some discussions, where neither the army and air force, nor the navy, felt ready for a decisive battle, the Führer directive No.6, issued on the 9th of October 1939, lined up a strategy where the main effort would be placed on a land battle aiming at a swift occupation of Netherlands, Belgium and as much of the French north coast as possible. Followed by an air offensive against Britain.
The strategy of the allies was less clear. Britain, and even more so France, was unwilling to fight a land battle at continental Europe. The feeling was that it would be a replay of the First World War, costing a lot in human life and economic loss, and with an uncertain end, as it would be fighting Germany where she was strongest. A blockade was on the other hand seen a less costly way of forcing Germany to peace. It would take time though, and with Soviet seemingly on the German side through the Molotov-Ribbentrop pact, it was hard to make it as effective as desired. In Britain there was a strong belief in the effectiveness of strategic bombing, and a number of plans was presented, for instance mining of the German canal system, which would hurt the German heavy industry. They were however all turned down by the French, as the German response would invariably hit France, and the French economy had the same weak spots as the German. The result was that the Allies didnt manage to decide about any substantial offensive actions on continental Europe.
In Britain there was discussions about the role of Scandinavia already from the beginning of the war. Especially Winston Churchill, who took a seat in the cabinet at the outbreak of the war, was a warm believer of a Scandinavian strategy. The logic of such a strategy was clear.
Steps toward invasion
The British foreign minister explains, while on visit in Sweden, that Britain in case of war with Germany might be forced to treat Sweden as an enemy, and make military actions in order to stop Swedish export of iron ore to Germany.
1 Sept 1939
Germany attacks Poland.
3 Sept 1939
Britain and France declares war on Germany
Churchill takes place in the British War Cabinet. He declares that he believes that Scandinavia and the Baltic Sea will be theatres of war for Britain.
Middle of Sept 1939
Churchill presents the plans for "Operation Catherine" for the War Cabinet. It is plans for taking a bigger fleet of capital ships into the Baltic Sea at the late winter of 1940 (Mars perhaps).
9 Oct 1939
Hitler issues Fuehrer directive No.6, stating that the main effort of Germany will be put into a land offensive through Belgium and Netherlands.
10 Oct 1939
The German Grossadmiral Raeder of the German navy discusses with Hitler the taking of bases in Norway, as well as the danger British bases there would pose. Other branches are not interested, and the naval operational department (???) is reluctant because of the difficulties involved.
16 Oct 1939
Hitler explains for Sven Hedin that he is very disappointed with the stance of the Scandinavian countries, which he feels always counteract German interests. In particular in the League of Nations, the antifascist stance of most Scandinavian newspapers and the trouble Germany had to get the import agreements they wished.
End of Nov 1939
Churchill proposes mining of Norwegian waters (to force ore transport ships into international waters where the British fleet might take care of them). He is turned down as Chamberlain and Halifax fears for the reactions in USA and among the small countries that Britain claims to be the protector of. The planned operation is later (?) named Operation Wilfred
30 Nov 1939
Soviet attacks Finland (The beginning of the winter war).
This changes the diplomatic and strategic picture a great deal. The Allies feels that this might be a possibility to get the Scandinavian countries on the Allied side. One hope was that Sweden and Norway would turn to Britain for protection (as Germany was "allied" with Soviet at that time).
Churchill makes new proposals for mining of Norwegian waters, or send in destroyers to attack the shipping, but is turned down.
The group around Raeder, lobbying for the occupation of Norway, gets in contact with the Norwegian Nazi leader Vidkun Quisling, and arranges a meeting between him and Hitler. Hitler gets the impression that he may count on the support from a significant fifth column in Norway if he would attack.
Britain signs a trade agreement with Sweden that allows Sweden to export 10 Million tons of ore to Germany annually.
14 Dec 1939
Alfred Jodl, head of OKW, is ordered by Hitler to make plans for the occupation of Norway.
The League of Nations expels Soviet and urges all member states to give what help they can to Finland.
Planning for sending of an expeditionary force to Finland through Narvik and the ore fields (and then destroy the ore fields) begins, as well as plans for how to counter German landings in southern Norway. The decree from the League of Nations would be kind of door opener in the Scandinavian states.
19 Dec 1939
French proposal for landing a larger expeditionary force in northern Norway.
They see a number of benefits with such an action:
This plan did presume co-operation from Norway and Sweden.
Here I make a pause to discuss the different personalities involved, and their different goals.
Chamberlain was a classical dove. He seems to have regarded the declaration of war on Germany as an ultimate diplomatic gesture. He did not wish to see any full scale war break out, but hoped that Germany, when realizing they had started a world war, would back down and hopefully remove that Adolf H. from power. He was also legalistic, i.e. thought that international law would be followed, and concerned about international reactions if they were not.
Halifax was of about the same opinions as Chamberlain.
Churchill was as much a hawk as Chamberlain was a dove. He felt that the ends justified the means and wouldn't hesitate to much to attack a neutral country to improve the positions in the great war. He wanted to act, not sit and wait. He saw the mining of Norwegian waters not only as a chance to disturb the ore traffic, but more importantly as a move that should provoke the Germans to a countermove in an area where the British would get the benefit from their superiority at sea. Hopefully the German actions (for instance an invasion in southern Sweden and Norway) would throw the Scandinavian countries into the allied arms.
The French administration under Daladier was quite content with the passive war, but they had a pressure from internal opinion to do something active against Germany. They were however very afraid of getting the war on to French soil, and were thus very reluctant to make any moves against the German homeland, as that might provoke German attacks on France. The opening of a second front where the war might be decided was more tempting.
The goal of Sweden (and probably Norway, but I have no information about their politics) was simply to stay out of all wars raging around them by all means. To accomplish this they tried to provoke as little as possible. Finland must be saved, but at the same time the winter war must be kept apart from the great war. If Finland became a battleground for the major powers it would be very difficult to keep Sweden out of it. Thus Sweden helped Finland as much as they dared, without being drawn into the conflict themselves, but did not support allied help to Finland. They also regarded anything that could disturb the ore shipments to Germany as dangerous, as the German reaction could be violent, and directed at Sweden.
While very skeptical vs. Churchill's plan to mine Norwegian waters, Chamberlain and Halifax were more positive toward the expeditionary force. It counted on co-operation with Norway, instead of conflict, so it wouldn't have the same legality problems. It might also be that they saw it as a method to keep Churchill at bay. Now the mining plan had to stand back, as it might interfere with the greater plan of sending an expeditionary force to Narvik. Mining Norwegian waters would reduce the chances to get Norwegian co-operation considerably.
In Germany various plans for actions in all the Scandinavian countries are prepared.
6 Jan 1940
Halifax sends memos to the Swedish and Norwegian governments, where he says that Britain might be forced to take military actions in Norwegian territorial waters as the Germans didn't respect the neutrality (they had sunk some ships in Norwegian waters). The reactions in Sweden and Norway are strong. Apart from the principles of violating the neutrality, they fear for the German reactions. In their answers they also points at the effect of the local opinions. The very negative reactions strengthens the skepticism of Chamberlain and Halifax toward Churchill's plans.
12 Jan 1940
The British cabinet once again turns down Churchill's request for Operation Wilfred (the mining of Norwegian waters), with the argument that it might interfere with the plan to send an expeditionary force to Narvik. Churchill was furious as he regarded the big plan as unrealistic.
20 Jan 1940
Churchill criticizes the neutral nations in a radio speech for bowing deep to Germany, knowing that France and Britain always followed international regulations, thus hoping to avoid the war. He says that the storm wont pass them though. The neutral nations reacts very negatively and Halifax banns Churchill for reducing the chances for co-operation from the neutrals.
end of Jan 1940
French proposal for landing a larger expeditionary force in Petsamo (northern Finland), thus eliminating the need for Swedish and Norwegian co-operation. The British was negative to this plan.
27 Jan 1940
The German plans for occupation of Norway is named Weserübung.
2 Feb 1940
Churchill says to a Swedish journalist that he wouldn't be displeased to see the war expand into a northern theatre.
5 Feb 1940
The allies decides in Paris to send an expeditionary force to Finland over Narvik and to take control of the Swedish iron ore mines at the same time. The force would consist of three to four divisions. The plans required the initial co-operation of Sweden and Norway. There was however at this time no sign whatsoever that they would co-operate. The military staffs realizes that they should send substantial forces to Trondheim and Namsos too. The force should be assembled by Mars the 20th.
The difference between those plans and reality is striking. A possible explanation is that Chamberlain and Halifax deliberately pushed for unrealistic plans, to avoid having to do what they regarded as dangerous and harmful actions, and still not give a too passive appearance.
16 Feb 1940
On Churchill's order HMS Cossack boards the German ship Altmark on Norwegian water and frees 300 British sailors. A Norwegian destroyer nearby doesn't interfere. Hitler sees this as a sign that the British wont respect the Norwegian neutrality, which makes him more committed to Weserübung.
18 Feb 1940
Churchill once again requests a mining operation on Norwegian waters. He is no longer turned down, but is given permission to prepare such an action.
21 Feb 1940
Gen. Falkenhorst becomes head of the staff that is planning Weserübung. The goals for the operation would be:
- A pre-emptive strike before the Allied did anything
- Secure the supply of iron ore
- Expand the base areas for the German navy and air force
Norway would be invaded while access to Danish airfields would be gained by diplomatic pressure.
23 Feb 1940
Finland requests Sweden and Norway to grant transit rights for foreign troops.
27 Feb 1940
Sweden and Norway declines the Finnish request.
During the spring Germany gets reports about an invasion fleet being assembled at the Scottish naval bases.
1 Mars 1940
The formal directives for Weserübung is issued by Hitler. In the directives both Norway AND Denmark are to be occupied. As few troops as possible should be used and maximum surpass should be achieved with all means available. If possible the operation should be done as a peaceful occupation.
The Finnish government asks the allied countries if they could immediately send 50 000 men and 100 bombers (to be able to continue the war). The allies can't accomplish anything like that, and Chamberlain is reluctant to promise anything, but Daladier promises it right away to keep Finland from ending the war.
2 Mars 1940
A formal request by Britain and France to Sweden and Norway to grant transit rights for an expeditionary force. The request is declined.
5 Mars 1940
The Finnish government decides to begin peace negotiations with Soviet.
10 Mars 1940
Weserübung might be started within 10 days. Jodl is worried that the end of the Winter war might make Weserübung hard to motivate (the source does not elaborate on if it was internally or externally).
12 Mars 1940
The British decides to immediately send an expeditionary force to Narvik. The commanders were ordered to avoid using force as long as possible. They have no permission to enter Norway or Sweden, and as it would be very difficult to get into Sweden by force (mountains and a single rail track - no roads) they must have hoped that, when the British troops already were on Norwegian soil, the Swedish and Norwegian governments would accept the situation and let the troops pass.
13 Mars 1940
The embarkation of the British expeditionary force to Narvik begins.
End of the Winter war is officially declared.
Jodl writes in his diary that Hitler looked for a new motivation for Weserübung.
14 Mars 1940
Due to the end of the Winter war the expeditionary force is recalled, and the organization built up for it is promptly disbanded.
18 Mars 1940
Churchill proposes that carriers should launch a strike against the Swedish port Luleå (the main port for shipping the ore from the ore fields around Kiruna and Gällivare).
20 Mars 1940
In France the Daladier administration falls (much due to the inability to help Finland). The new administration is led by Paul Reynaud. The new government has an activist line in the war against Germany (as long as it wouldn't provoke a German attack on France), and immediately brings forward the possibility of an action against Narvik.
Chamberlain and Halifax also feels the need to take some initiative in the war, so the mining of Norwegian waters was again discussed. They did however feel strongly that it wouldn't be good for Britain's reputation if the first offensive action taken by the defender of the small nations (that was what they had gone to war for after all) would be directed at one of these small nations instead of directly at Germany. Another offensive plan put forward by Churchill earlier was mining of the internal waterways in Germany (important for the German industry). It was called Operation Royal Marine. Now Chamberlain required that Operation Royal Marine would be done simultaneously with Operation Wilfred to show that the Allied countries DID fight Germany too.
28 Mars 1940
The Allied war council decides to proceed with Operation Royal Marine the 4:th of April and Operation Wilfred the day after. The French delegation had some reservations about Op. Royal Marine though.
29 Mars 1940
The British cabinet decides that Op. Wilfred will be followed by troop landings in important Norwegian ports (Stavanger, Bergen, Trondheim and Narvik). Not many troops were available for this at this moment though.
31 Mars 1940
The French government says that it will not support Op. Royal Marine as they fear German reactions. France is at least as dependent on its internal waterways as Germany. They were however still very interested in an action against Norway.
2 April 1940
Hitler decides that the attack will start on the 9th of April, without any declaration of war.
The Swedish foreign minister asks his German counterpart about German troop concentrations at the Baltic ports, without getting any real answer.
3 April 1940
After a struggle between Chamberlain and Churchill the British cabinet decides to do Op. Wilfred even if the French wont accept Op. Royal Marine. Chamberlain sends Churchill to France to try to make them change their mind.
The first German ships leaves German ports for Norway.
5 April 1940
To avoid further delay of Op. Wilfred, Churchill tells Chamberlain that the French is right about wanting to postpone Op. Royal Marine!
The British cabinet decides to do Op. Wilfred on the 8th of April.
8 April 1940
British destroyers lays a minefield on Norwegian waters south of Narvik.
The expeditionary force embarks onto warships at the Scottish bases.
9 April 1940
German troops lands in most important ports in Norway and Denmark.
The British expeditionary force makes a hasty debarkation as it is decided that the warships shall attack the German fleet that is reported to try a break out.