He was 43 years old when he enlisted (2, 6, 8 [57 at death in 1865]). He was born in Armagh, Ireland (2 [Omor], 6 [Armah]).
He was a gardener or laborer when he was enlisted (2 [laborer], 6 [gardener]).
He was 5 feet 6-1/2 inches tall, had a dark complexion, blue eyes, and dark hair (2 [5'6-1/2", dark complexion, blue eyes, dark hair], 6 [5'6-1/2", light complexion, blue eyes, dark brown hair]).
He enlisted and was mustered into service for three years in company E on 31 August 1861, at Philadelphia Pennsylvania (1, 2, 6). He was enlisted by Captain Lentz, and mustered in by Captain Starr (2, 6).
He was transferred on 28 December 1862 to company G, by regimental order, because company E was over the maximum (1, 2, 3).
He was wounded on 3 May 1863 at Chancellorsville, Virginia (1, 4, 7).
He reenlisted as a veteran volunteer (1).
He died suddenly on 26 April 1865 in Philadelphia Pennsylvania, of unknown causes (1, 5, 8 [25 Apr]). The coroner held an inquest on his death (5). He was buried in the city burial ground (8).
1 Bates, Samuel Penniman. History of Pennsylvania volunteers, 1861-5. Harrisburg: B. Singerly, state printer, 1869-71. 5 volumes. 'Ninety-first regiment', volume 3, pages 186-233. (In the roster)
2 descriptive roll, company E, entry 79
3 register of men transferred, company E, entry 5
4 consolidated morning report, 91st PA, 7 May 1863 (Private Williamson)
5 company G, register of deaths (Samuel Williamson)
6 company G, descriptive roll, #80 (Samuel Williamson)
7 'Further from General Hooker's army', Philadelphia Inquirer, 7 May 1863, page 1 (S Williamson)
8 death certificate, Philadelphia, Pennsylvania, 25 April 1865 (Samuel Williamson)
[I did not find an entry for him in the Ancestry index to the pension index by name (searched April 2007)]