Images and Pictures of the German Invasion of Denmark   German Invasion of Norway (April 9, 1940)--Germany invaded Norway and Denmark on April 9, 1940, in order to secure Norwegian routes for the Swedish iron ore that German industry needed for Hitler's war. German troops conducted a swift and very easy invasion and occupation of Denmark by both the sea and the ground, swiftly occupying Denmark. See also: German Invasion of Poland (1939) , Video and Film of the German Invasion of Poland (1939) and the Images and Pictures of the German Invasion of Denmark (1940)     German Ju-52 transport planes over Denmark on the morning of April 9, 1940   German troops are airlifted into the Aalborg airport      German tanks in Denmark, 1940.   German planes drop propaganda over Copenhagen, Denmark, 1940.   Danish King Christian X During World War Two.