The Danish flag, called “Dannebrog” (Danish piece of cloth or flag or banner), is the oldest known national flag in the world. The white cross on a red background does not refer exclusively to Christianity, but to a universal symbol from ancient times.
According to the legend, the “Dannebrog” fell from the skies on 15th June 1219, when the crusader King Valdemar II (the Victorious) defeated the pagan Estonians in a famous battle. The first use of the “Dannebrog” as a flag would have happened some one hundred years later.
During its descent, the “Dannebrog” has drawn a vertical axis linking Heaven and Earth and symbolizing the various being's states from the most celestial to the most terrestrial. By falling on the horizontal ground, it made a cross. The horizontal branch corresponds to the amplitude of the entire possibilities linked to a specific state of being.
The white colour of the cross is associated with the whole spectrum of the visible light emerging from the invisible Principle represented by God. At the top of the spectrum of the rainbow colours, red may be related to the first representative of the manifestation order, the King, acting under the guidance of God.
A swallowed-tailed pennon was reserved to the naval fleet by a 1630 decree. Its use was formerly forbidden to all merchant ships in 1635. Since then, the authorities got used to hoist the swallowed-tailed pennon on dry land. In 1748, it was definitively decided that merchant ships would fly the rectangular flag.
As a general rule, the swallowed-tailed pennon is reserved to the royal family and State authorities; individuals may only use the rectangular flag.