Mons Hendriksen Lie

I am trying to find what eventually happened to my great, great grandfather. He was born at Evanger, Hordaland, Norway in 1796 and married Ingeborg Askjelddtr in 1828. They had at least 2 children Henrik 1844 and Ingeborg somewhat later. They emigrated to America about 1856. We think they went first to Wisconsin and then to Iowa. Hendrik joined the Union Army in 1864 from Iowa. We think Mons died in about 1863, but have been unable to find any evidence that he ever lived in the US. Would appreciate any help.