Norwegian patronymics, or how the Eilertsens got their name

Norwegian patronymics, or how the Eilertsens got their name

Not knowing much about Scandinavian surname etymologies, I was surprised to learn that Eilert is actually a given name and that Eilertsen was a surname assigned to someone who was a son of Eilert. 

This becomes quickly clear when you review the ancestry of Jacob Eilertsen, the Norwegian-born father of Edwin and Clarence Eilertsen. Jacob's ancestry going back several generations is readily discoverable using vital records and family trees on Ancestry.com,

Jacob's father was Eilert Osmundsen, his grandfather was Osmund Erickssen, and his great grandfather was Erik Torkildsen. 

If Ed Eilertsen had been born in the old country and named in the traditional way, he would have been named Edwin Jacobsen. Instead the line of patronymic naming in the family ended after Jacob settled in New York. 

When Ed was born in March 1925, he was named according to the American custom and was given the inherited last name of his father Jacob Eilertsen. Thus, he was named Ed Eilertsen instead of Ed Jacobsen. 

Actually, Norway also adopted heritable surnames in 1923, so he would have still have grown up with the Eilertsen name even if he had been born in Farsund.

By the way, patronymic naming applied to girls as well, but they got the suffix of dater or datter (daughter), instead of sen (son). Thus, Eilert Osmundsen was married to Johanna Marie Jacobsdater, for example. After marriage, Norwegian wives took their husband's surname.