On April 9 of 1940 at 4:15am, Germany invaded Denmark as part of the Operation "Weseruebung" directed towards the invasion of Norway. German invasion was to "protect" Denmark against the British attack.
"(Special Information) In order to counter British preparations to take away the neutrality of Denmark and Norway, German Wehrmacht took over armed defence of both nations." – OKW message from Tuesday, April 9th of 1940.
Upon receiving reports about German invasion plans on April 4 of 1940 and the grouping of German Fleet in the Danish waters, Danish Fleet was ordered not to engage the enemy. This allowed the Germans to make landings without any resistance.
Danish Army was not in a position to challenge the German Army, because it only consisted of two infantry divisions (Zealand and Jutland), totally unprepared for war, since mobilization began on April 8 of 1940. As of April of 1940, the army had some 9900 to 14000 men under arms including 8000 men drafted during previous two months. Danish Fleet had only two coastal defense vessels dating to 1906 and 1918 along with 17 torpedo boats, 12 submarines and consisted of 2150 to 3000 men. Danish airforce had some 50 to 110 obsolete planes divided between the navy and the land forces with some 800 men. Danish Army did not possess any operational tanks although it had tested Italian Fiat 3000B in early 1920s, French Renault NC2 (NC.31) and British Vickers-Armstrong Carden-Loyd Patrol Mk.II in early 1930s. In addition, there were Copenhagen’s coastal defenses and minefields. Opposing the Danish Army was German XXI Corps (composed of two infantry divisions and supporting units), commanded by Nikolaus von Falkenhorst.
At 5:00am, German paratroopers landed at abandoned fortress of Madneso and soon after at the airport of Aalborg. At 6:00am, German sea transport arrived at the port of Copenhagen and single infantry division entered Jutland. Defeated from the start Danish Army did not put up any resistance with the exception of fighting in North Schleswig and for the Royal Palace in Copenhagen. At 9:20am, under the threat of aerial bombardments of Copenhagen, Danish government ordered cease-fire, protested against the occupation and then surrendered. By the end of the day, Germany controlled entire Denmark.
In conclusion, Danish casualties consisted of 12 pilots, 11 soldiers and 3 border guards along with 23 wounded. German losses are unknown but were probably higher. The occupation of Denmark provided Germany with bases for operations on the North Sea and Atlantic as well as aerial operations against England. It also secured supplies of Swedish steel by the sea. The occupation of Denmark was also an important factor in securing the Northern Europe in upcoming invasion of Low Countries and France in May of 1940.
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