Historisk Tidsskrift
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Summary:

Christian Paulin

Pathways to Strategic Control over Denmark
German Plans for a Pre-emptive Attack, 1916-18

(109:2, 457-458)

German plans to attack neutral Denmark during the First World War were never actually carried out. Perhaps for the same reason no one, until today, have bothered to analyse them in their own right. Two earlier studies focus, respectively, on diplomatic relations between the two countries and on patterns of power struggle within the German armed forces. The present study, based on systematic use of relevant archival sources, specifies the strategic and tactical considerations by German officers, while at the same time placing the successive shifts in the operational scenario within a general politico-military context.

From 1916 onward, German plans to attack and occupy Danish territory were a realistic prospect. The transformation from vague notion to explicit, well-considered scenario proceeded in two phases. In the beginning, the justification was essentially reactive and defensive. The purpose was to counter a Danish attack or an intrusion of the Royal Navy into Danish waters. The first possibility might seem remote, but Romania’s entry into the war on the side of the Entente in the summer of 1916 had shown the latent opportunism of even a weak, neutral state. The fear was that maritime trade-dependent Denmark, following the German resumption of unrestricted submarine warfare in 1916-17, would launch an attack on Germany’s northern flank with British support.

In May 1917, the army agreed to make troops available for a possible Northern front. This was a move towards a second and more offensive phase of German planning. The escalation became effective with a revised plan of operations in spring 1918. An attack was no longer premised on the Danish/British menace, but would serve broader purposes. The more radical admirals in the German Navy had long pushed for this shift. In order to improve Germany’s geo-strategic position and challenge Britain’s maritime supremacy they intended to carry out flanking operations from naval bases in the North Sea region.

Eventually, German army strategists would yield and commit resources to the scheme of the admirals. However, this was a pragmatic reaction; they remained unconvinced that a pre-emptive attack on Denmark was worth the effort. Therefore, the overarching idea of the German plan of operations was to force the Danish government to surrender, employing low-risk naval operations only. These included minelaying, destruction of communication cables, naval bombardment and air attacks. However, the idea of a naval bombardment of Copenhagen was abandoned due to the strong fortifications.

Besides cautiousness at the operational level, there were two important reasons why the attack on Denmark was never realized. Great differences of opinion persisted between the German military and civil bureaucracies. The German Foreign Ministry found that use of military force was unnecessary. It strongly opposed the idea of an unprovoked pre-emptive strike against a neutral country. This was largely because of the propaganda failure following the German invasion of neutral Belgium in 1914. It seems that the German ambassador to Copenhagen, Brockdorff-Rantzau, eventually convinced German military authorities of Denmark’s loyalty – and of the fact that he, Brockdorff-Rantzau, had the situation under control. His secret deliberations with Danish Foreign Minister Scavenius on matters of military intelligence were of great

[p. 458]

importance. The combined appeasement strategies of the top diplomats on both sides thus never offered the German Navy a pretext for invasion based on Danish disloyalty. Nevertheless, the Foreign Ministry’s power vis-à-vis the military was on the wane towards the end of the war.

At the structural level, one probable reason why the contingency plans were never triggered was that neither of the great powers had the necessary resources to open a new front. The balance of power prevented the attack.

The lack of unity among German decision-makers was important in the first phase. Later, troops were in fact assigned for the operations, but petty quarrels over command structure persisted. The civil administration counteracted the plans of attack, but was finally outmanoeuvred. The operational plans now took an activist, offensive turn. However, in March-April 1918 the great offensive on the western front petered out. The defensive warfare of the following months left no additional personnel available for an attack on Denmark, be it pre-emptive or strategically offensive. The window of opportunity was no longer open.

Still, the plans to attack Denmark hibernated in the German navy and were implemented in April 1940 – this time without a hitch.