In that case, Harald built six fortresses around Denmark called Trelleborg and built a further Danevirke.
In the early 11th century, Canute the Great won and united Denmark, England, and Norway for almost 30 years with a Scandinavian army.
Denmark became a member of the European Economic Community (now the EU) in 1973, maintaining certain opt-outs; it retains its own currency, the krone.
They colonised, raided, and traded in all parts of Europe.
The Danish Vikings were most active in the eastern and southern British Isles and Western Europe.
Beginning in the 17th century, there were several cessions of territory to Sweden.
In the 19th century there was a surge of nationalist movements, which were defeated in the 1864 Second Schleswig War. In April 1940, a German invasion saw brief military skirmishes while the Danish resistance movement was active from 1943 until the German surrender in May 1945.
Most handbooks derive the first part of the word, and the name of the people, from a word meaning "flat land", The Nordic Bronze Age (1800–600 BC) in Denmark was marked by burial mounds, which left an abundance of findings including lurs and the Sun Chariot.