Among Scandinavian countries which Denmark is part of, adoption of heritable family names was quite common. The usual practice was to use the surname together with a primary patronym. This meant using the father’s name plus a suffix denoting relationship for son or daughter.
Some of the patronymic suffixes often used are -son, -sen, -sson, -zen, -zon/zoon, and -ssen. In Denmark, the most common surnames follow this naming tradition. The top ten in the country includes Jensen, Nielsen, Hansen, Pedersen, Andersen, Christensen, Larsen, Sørensen, Rasmussen, and Jørgensen. Thus a child with a surname Jensen is taken to mean as a son of Jens.
Heritable names were made compulsory for nobility as provided in the first naming act in Denmark in 1526. This resulted to most people choosing to adopt a heritable family name which in turn resulted to an overwhelming dominance of a few surnames. Later naming acts would encourage people to change their surnames to less-frequently used ones for the purpose of safer identification. Even then, the popularity of traditional names persists up to the present. Only one surname of German origin and one of Swedish origin have made it to the top 100 list of most common names in Denmark. The rest are traditional surnames.
As to the first names given to children, there are several identified favorites. For boys, the top ten are William, Lucas, Victor, Noah, Oscar, Liam, Frederik, Emil, Oliver, and Magnus. The top ten choices for girls include Sofia, Ida, Freja, Emma. Isabella, Sofie, Maja, Laura, Clara, and Mathilde.