IA Sioux City Cav Co ?. Residence: Spirit Lake, Iowa. Born in Avaldsnæs, Norway. Civil War: Age 22. Enlisted 24 Sep 1861, into the Sioux City Volunteer Cavalry Company. Mustered 18 Nov 1861. Private. Transferred into the Iowa Seventh Cavalry, Co I, on 14 Jul 1863. Mustered out 23 Nov 1864, Sioux City, Iowa. Post war: In 1885, Gunder Mathewson was living in Milford, Iowa. Sources: (ISW-IV p1342, 1777) (XSS Iowa p208) (Ulvestad p309)