Denmark in World War II

At the outset of World War II in September 1939, Denmark declared itself neutral, but that neutrality did not prevent Nazi Germany from occupying the country soon after the outbreak of war; the occupation lasted until Germany's defeat. The decision to occupy Denmark was taken in Berlin on 17 December 1939. On 9 April 1940, Germany invaded Denmark in Operation Weserübung. In contrast to the situation in other countries under German occupation, most Danish institutions continued to function relatively normally until 1945. Both the Danish government and King of Denmark remained in the country in an uneasy coalition between a democratic system and a totalitarian one until, amidst growing civilian resistance and unrest, the Danish government refused to further cooperate with the Germans' demands; in response, on 29 August 1943, Germany declared martial law and placed Denmark under direct military occupation, which lasted until the Allied victory on 5 May 1945.

The German occupation of Denmark formed part of Berlin's broader strategic plans in northern Europe. Denmark occupied an important geographic position as the gateway to the Baltic Sea and as a transit route between Germany and occupied Norway. Control of Danish airfields and ports enabled German forces to support naval and air operations in the North Sea and the North Atlantic. The occupation was also intended to secure agricultural production and maintain stable deliveries of food products to Germany during wartime shortages.

During the first years of occupation, the Danish policy of cooperation (samarbejdspolitikken) was defended by politicians as a means of preserving a degree of national autonomy and protecting the population from harsher German measures.