[5] In 1521, king Christian II of Denmark invited 184 Dutch farmers to settle on the island of Amager in exchange for supplying the Palace of Copenhagen with vegetables.

The Dutch immigrants were exempt from Danish taxation and were given privileges such as being allowed to hunt most wild animals and having their own judicial system until 1823.

Emperor Charles V of the Holy Roman Empire supported Frederick II, Elector Palatine for the Danish crown, and Denmark participated in the war on the side of France.

Secondly, the Belts froze over in a rare occurrence during the winter of 1657–1658, allowing Charles X Gustav of Sweden to lead his armies across the ice to invade Zealand.

In the Treaty of Roskilde, Denmark-Norway capitulated and in panic gave up all of Eastern Denmark in addition to the counties of Bahusia and Trøndelag in Norway.

Three months after the peace treaty was signed, Charles X Gustav of Sweden held a council of war where he decided to simply wipe Denmark from the map and unite all of Scandinavia under his rule.

Frederick III of Denmark had stayed in his capital and now encouraged the citizens of Copenhagen to resist the Swedes, by saying he would die in his nest.

Following his death, Sweden made peace in the Treaty of Copenhagen, returning only Trøndelag to Norway and Bornholm to Denmark, but keeping both Bahusia and Terra Scania, mainly because the Netherlands and other European powers didn't want both sides of the Sound controlled by the Danish King again.

England's Royal Navy joined France in its attack on the Republic, but was frustrated in its attempts to blockade the Dutch coast by four strategic victories by Lieutenant-Admiral Michiel de Ruyter.

Parliament, fearful that the alliance with France was part of a plot to make England Roman Catholic, forced the king to abandon the costly and fruitless war.

Although the Danish offensive was initially a great success, Swedish counter-offensives led by the 19-year-old Charles XI of Sweden nullified much of the gain.

The war and the hostilities ended when Denmark's ally the Dutch Republic settled with Sweden's stronger ally France and the Swedish king Charles XI married Danish princess Ulrike Eleonora, sister of Christian V. Peace was made on behalf of France with the treaties of Fontainebleau and Lund and Saint Germain, restoring most of the lost territories to Sweden.

[27] These specially directed measures were accompanied by more general ones: the Dutch had posted no less than 32 hospital ships throughout the country and fifteen trains to help make troop movements easier.

In August 2010, the Royal Dutch Army sent HNLMS Zierikzee for a NATO naval task force exercise in Denmark.