Germany invoked this treaty on 9 April 1940, when it ordered the military occupation of Denmark under the guise of protecting the Danes from British invasion.

Faced with potential German aerial bombing, King Christian X and the Danish government accepted "protection of the Reich" and permitted the "peaceful occupation" of the country in return for nominal political independence.

On 29 June 1941, seven days after the invasion had begun, the Danish Nazi Party newspaper Fædrelandet ("The Fatherland") proclaimed the creation of the Free Corps Denmark.

Colonel Christian Peder Kryssing, Chief of the 5th Artillery Regiment, Holbæk, has with the consent of the Royal Danish Government assumed command over Free Corps Denmark."

Some authorities maintain that the Corps was unique among the legions of foreign volunteers fighting for Hitler in that it carried the official sanction of its home government.

On 8 May 1942, the corps was ordered to the front line where it engaged in fighting near Demyansk, south of Lake Ilmen and Novgorod.

In December, the corps engaged in intense fighting at the Battle of Velikiye Luki alongside Germany's 1st SS Infantry Brigade.

[4] It was reformed as SS-Panzergrenadier Regiment 24 "Denmark" (SS-Panzergrenadier-Regiment 24 "Danmark") and integrated into the recently formed 11th SS Volunteer Panzergrenadier Division Nordland.