Portrait of John Williamson, post war, c.1890. Calhoun County. Enlisted in company F, Sixteenth Infantry, Aug. 2, 1861, at Plymouth, for 3 years, age 21. Mustered Sept. 7, 1861. Discharged at expiration of term of service at Petersburg, Va., Sept. 7, 1864 (Descriptive Roll Sixteenth Michigan Volunteers).