First time Denmark is mentioned by name is in a letter by Bishop Ansgar written in the mid 9th century. During the Viking period Denmark became a great power and was united with England for almost 30 years in the early 11th century.

Pre-Union

The Danish king Valdemar Atterdag had a daughter, Margaret I, who was married to the Norwegian king in an attempt to unify the two kingdoms. Through several political disturbances in both Norway and Sweden in the late 14th century she took her chance and managed to become ruler of Sweden, Norway and Denmark since her son, Olav III died at an early age.

Union Ruler

Eric of Pomerania who was the Queens successor failed in his ruling skills and managed to more or less break up the union but was managed to be held intact by the next person who entered the throne. During the almost 130 year long union, the Swedes felt mistreated since the majority of power lied in Denmark and a nationalistic feeling started to rise in Sweden with a demand to break the union. Danish King Kristian II enters Stockholm in 1520 to be coronate as the new king in the union and directly afterwards he executes what is to be known as “The Bloodbath of Stockholm”.

The bloodbath didn’t help Kristan´s attempt to unify the union again but manage to put more wood on the nationalistic fire.

Post Union

When Sweden managed to break the union in 1523 after an independence war, civil war broke out in both Denmark and Norway but it didn’t take long before Denmark and Norway was bounded in another union again with Danish ruling. The 16th century also made Denmark to grow to a powerful and wealthy nation since it controlled both sides of Öresund making them tax any trade traffic passing through. Even though Norway lost big pieces of its country to Sweden in several peace treaties during the mid 17th century the economy rose and the Danish king took bigger interest in Norway.

Napoleon Wars

During the Napoleon Wars, Denmark in the union with Norway, tried to keep a neutral line. United Kingdom demanded that the Danish fleet would be handed over and the crown prince refused which led to United Kingdoms attacked Copenhagen in 1801.

Denmark joined forces with France and United Kingdom attacked Copenhagen again in 1807. When the allied forces finally managed to defeat Napoleon in 1814, Denmark had to give over Norway to the king of Sweden in the peace treaty signed in Kiel.

Monarchy and Monetary Union

Denmark became a constitutional monarchy in 1849 and to avoid any bloody revolution King Frederick VII gave in to the people’s demand of having a share in the government. In 1873 a new union was formed between Sweden and Denmark this time to bring their currencies together and Norway joined in two years later. The currencies name was decided to be called Krone/Krona (Crown) and all countries issued their own coins but it was valid as payment in the whole region. The union was dissolved in 1914 when the WW I broke out in Europe.

Wartime

Denmark stood neutral in WW I but was effected since a part of Denmark was in borders with the German Empire and when the peace in Versailles was signed Germany had to give up some of its border area to Denmark. In the outbreak of WW II, Denmark once again declared neutrality and signed a non-aggression agreement with Nazi Germany, who in the spring of 1940 occupied Denmark anyway and held it occupied throughout the whole war. During the war in 1944, Iceland became a fully independent republic; previously the Danish monarch had been King over Iceland as well.

Post War

Faroe Islands was granted home rule in 1948 and Greenland got colonial status in 1953. Denmark abandoned their policy of neutrality and became a member of United Nations. They entered European Union in 1973.