On 27 January 1940 a memorandum was prepared by the Defendant Keitel regarding the plans for the invasion of Norway. On 28 February 1940 the Defendant Jodl entered in his diary: “I proposed first to the Chief of OKW and then to the Führer that Case Yellow (that is the operation against the Netherlands) and Weser Exercise (that is the operation against Norway and Denmark) must be prepared in such a way that they will be independent of one another as regards both time and forces employed.”
On 1 March Hitler issued a directive regarding the Weser Exercise which contained the words:
“The development of the situation in Scandinavia requires the making of all preparations for the occupation of Denmark and Norway by a part of the German Armed Forces. This operation should prevent British encroachment on Scandinavia and the Baltic; further, it should guarantee our ore base in Sweden and give our Navy and Air Force a wider start line against Britain . . . . The crossing of the Danish border and the landings in Norway must take place simultaneously . . . . It is most important that the Scandinavian States as well as the Western opponents should be taken by surprise by our measures.”
On 24 March the naval operation orders for the Weser Exercise were issued, and on 30 March the Defendant Dönitz as Commander-in-Chief of U-boats issued his operational order for the occupation of Denmark and Norway. On 9 April 1940 the German forces invaded Norway and Denmark.
From this narrative it is clear that as early as October 1939 the question of invading Norway was under consideration. The defense that has been made here is that Germany was compelled to attack Norway to forestall an Allied invasion, and her action was therefore preventive.
It must be remembered that preventive action in foreign territory is justified only in case of “an instant and overwhelming necessity for self-defense, leaving no choice of means, and no moment of deliberation” (The Caroline Case, Moore’s Digest of International Law, II, 412). How widely the view was held in influential German circles that the Allies intended to occupy Norway cannot be determined with exactitude. Quisling asserted that the Allies would intervene in Norway with the tacit consent of the Norwegian Government. The German Legation at Oslo disagreed with this view, although the Naval Attaché at that Legation shared it.
The War Diary of the German Naval Operations Staff for 13 January 1940 stated that the Chief of the Naval Operations Staff thought that the most favorable solution would be the maintenance of the neutrality of Norway, but he harbored the firm conviction that England intended to occupy Norway in the near future relying on the tacit agreement of the Norwegian Government.
The directive of Hitler issued on 1 March 1940 for the attack on Denmark and Norway stated that the operation “should prevent British encroachment on Scandinavia and the Baltic.”
It is, however, to be remembered that the Defendant Raeder’s memorandum of 3 October 1939 makes no reference to forestalling the Allies, but is based upon “the aim of improving our strategical and operational position.”
The memorandum itself is headed “Gaining of Bases in Norway”. The same observation applies mutatis mutandis to the memorandum of the Defendant Dönitz of 9 October 1939.