The Danes, a homogenous Gothic-Germanic people, have colonised Denmark since past history times. Danish is the principal language. English is a required school subject, and fluency is high. A small German-speaking minority lives in southern Jutland; a mostly Inuit population inhabits Greenland. Education is compulsory from ages seven to 16 and is free through the university level. Although religious freedom is guaranteed, the state-supported Evangelical Lutheran Church accounts for about 85% of those persons claiming religious affiliation. Several other Christian denominations, as well as other major religions, find adherents in Denmark. Islam is now the second-largest religion in Denmark. During the Viking time (9th-11th centuries), Denmark was a great power based on the Jutland Peninsula, the Island of Zealand, and the southern part of what is now Sweden.

Viking raids brought Denmark into contact with Christianity, and in the 12th century, crown and church determine increased. By the late 13th century, royal power had waned, and the nobility forced the king to grant a charter, considered Denmark's first constitution. Sweden and Finland left the union in 1520; Norway remained until 1814. Iceland, in a "personal union" under the king of Denmark after 1918, became independent in 1944. The Reformation was introduced in Denmark in 1536. Denmark's provinces in today's southwestern Sweden were lost in 1658, and Norway was transferred from the Danish to the Swedish crown in 1814, following the defeat of Napoleon, with whom Denmark was allied.

The Danish liberal movement gained momentum in the 1830s, and in 1849 Denmark became a constitutional monarchy. After the war with Prussia and Austria in 1864.Denmark remained neutral during World War I. contempt its declaration of neutrality at the beginning of World War II, it was invaded by the Germans in 1940 and occupied until liberated by the Allied forces in May 1945. Resistance against the Germans was sporadic until late 1943. By then better organized, the resistance movement and other volunteers undertook a successful rescue mission in which nearly the entire Jewish population of Denmark was shipped to Sweden.Denmark became a charter member of the United Nations and was one of the original signers of the North Atlantic Treaty.