Denmark has the world’s oldest known national flag still in use, the Dannebrog. The flag is a red field with a white Scandinavian cross extending to its edges. Its current design has been used for centuries, and Denmark’s flag tradition is documented from the medieval period.
According to Danish legend, the Dannebrog fell from the sky during the Battle of Valdemar in Estonia on 15 June 1219. The story says that its appearance helped Danish forces win. Historians treat the legend cautiously, because the earliest surviving written accounts appeared much later.
The Scandinavian cross became a defining feature of flags across the Nordic region. Sweden, Norway, Finland and Iceland all use related cross designs, but their flags were adopted later. Denmark also uses the flag in distinctive forms for royal, naval and state purposes.