You say Arne died about 1929, but his wife is already listed as a widow in the 1920 census. The 1910 census says Arne arrived in America in 1876. Arne is already living in Waterloo, Iowa in the 1880 census, so he ws there long before 1885.
According to the 1900 census, Arne was born Sep 1857 and arrived in America in 1867. The 1915 census says Arne J. Overhaug arrived in America about 1879, so I believe the date 1876 is closer to being correct than 1867.