Knut was the son of Gunar Toreson Havajuvet of Norway (1809-1867) and Martha Knutsdatter Hagen (1812-1901). He married Gunne K. Jakobsdatter Prestegard (1842-1907) in 1864 in Norway. They immigrated to Minnesota in 1867. They were the parents of eleven children. After Gunne died, Knut married in 1910, Ingrie Bjorngjeld (1854-1931).