Jensine Bergethe Jensen married Oliver Olsen in Chicago, Illinois on 3 July 1875. Both were from Norway.
The birth records of Jensine's children show that she was from Trondheim. Born about 1849 or 1850.
One birth record for Oliver Olsen's children shows he is from Kristiania (Oslo) but family info says Bergen. He was born about 1841.
When he died in 2 May 1891, it shows that he has been in the United States 20 years.
I have searched familysearch.org and those are the facts I've gotten. I did not find a 1890 census for Chicago, but the family is on the 1880 census. I have not found Jensine on the 1900 census.
They had a total of 6 children in Chicago, Cook county, Illinois, but those records did not help make the connection to the parents' identity in Norway.
It is possible that Jensine Bergethe (Bergithe?) came over earlier with her parents, just a guess, and that Jensen was not her patronym.
I would appreciate any help finding their roots in Norway.