Understanding Scandinavian Patronymic Surnames

By Diana Crisman Smith
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Patronymic surname suffixes throughout Scandinavia often changed depending on which country controlled the area. When researching your ancestors in Sweden, Norway or Denmark, it can be helpful to know when these changes to surnames occurred.

The naming trends on this chart hold true through most of the 18th and 19th centuries. As Scandinavian countries began requiring fixed surnames, families slowly began adopting and passing them on. Late in the 19th century many families, especially in Denmark, began using the male extension for both sons and daughters.

CountrySonDaughter
Denmark-sen-datter
Sweden-son-dotter
NorwayBefore 1814 (Danish rule): -sen
1814-1905 (Swedish rule): -son
After 1905 (independence): -sen
Before 1814: -datter
1814-1905: -dotter
After 1905: -dotter

Tip: Sometimes a record will show a female’s surname ending with –dtr. That’s just an abbreviation for the full extension, not the actual surname.

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