I couldn't find him in the 1880 US census. He immigrated after 1870 (I'm quite sure). He died in 1891, and there is no 1890 census.
I'm doing this research for a cousin. My cousin saw the gravestone which had that he was born in 1841. My cousin was told by his mother that Oliver was from Bergen, and the 1865 census for Arendal, Aust Agder, Norway had the fact that he was born in Bergen. THe information on the 1865 census was an exact match to the description I had been given for Oliver.
THe death record gave the fact that he was a machinist. On the 1865 census from Norway he was a smedsvend which could be adapted to being a machinist. He was never a farmer. He lived in Ilinois, was married and was buried in Mt. Olive cemetery. The death record did not give the names of the parents. I've asked my cousin to write for a death certificate. I don't know if he's done that yet.
Thank you ever so much for your interest in my query. We host a genealogy group at our house once a month. I continually stress at how great the message board it. People like you prove that fact. Thank you again.