He was born in Philadelphia, Pennsylvania (6, 7, 8, 9). He was 32 years old when he was enlisted (6, 7, 9 [55 in ?1885]).
He was a tailor when he was enlisted (6, 7).
He was 5 feet 9 inches tall, and had a light complexion, blue eyes, and brown hair (6, 7).
He also served in company E of the 25th Pennsylvania Infantry (8, 9, 10, 11). He served for three months (8).
He was enlisted and mustered into service on 21 December 1861 (1, 6, 7). He was enlisted for three years, at Philadelphia, Pennsylvania, by Captain Casner (6, 7). He was mustered in as a private in company K, perhaps by L T Mattack (1, 6, 7 [Lt D H Lentz).
He was severely wounded on 3 May 1863, and was sent to the hospital at Portsmouth Grove, Rhode Island (1, 2). He was reported missing in action on 7 May 1863 (3). On 19 May 1963, he was reported gained from missing in action (4).
He returned to the regiment on 23 April 1864, but was in poor enough condition that he had to be under the surgeon's care (2, 5). He was detailed to assist in the division hospital on 8 May 1864, and remained there until the wounded had been removed (2).
He was returned to the Portsmouth Grove hospital, and on 28 June 1864, the regiment had not heard from him (2). He had apparently been charged with desertion then, and his wife had requested that the charge be removed (2). Gregory supported her request (2).
He was discharged on 6 January 1865 by general order (1), or on 21 December 1864 at Philadelphia, Pennsylvania, when his term expired (12). He had served for twenty-seven months (9). The regiment was not notified until 20 April 1864 (12).
On 10 April 1867, he applied successfully for a pension (10, 11).
On 23 May 1885, he was admitted from Pennsylvania to the National Soldiers Home (9). He had a wound in his side, and was receiving a pension of $4 per month (9).
In 1885, he was living at the National Home for Disabled Volunteer Soldiers, Central Branch (8). He was admitted on 23 May 1885 (8). He was 55 years old (8). He had a wound in his right or left side (8). He received a pension of $4 per month (8).
On 14 April 1896, his widow, Hannah L Cooper, applied successfully from Pennsylvania for a pension (10, 11).
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 letter, Gregory to Breck, 28 June 1864
3 consolidated morning report, 91st PA, 7 May 1863 (Wm R Cooper)
4 consolidated morning report, 91st PA, 19 May 1863 (W R Cooper)
5 consolidated morning report, 91st Pennsylvania, 23 April 1864 (Cooper)
6 company K, descriptive roll (Wm R Cooper)
7 company K, third descriptive roll (William R Cooper)
8 National Home for Disabled Volunteer Soldiers. Report of Managers of the National Home for Disabled Volunteer Soldiers, transmitting the report of the said board for the year ending June 30, 1885. January 7, 1886. Serial Set volume 2415, session volume 10, 49th Congress, 1st Session, House Miscellaneous Document 38, page 173 (William R Cooper)
9 Letter from the President of the Board of Managers of the National Home for Disabled Volunteer Soldiers, transmitting the report of the Board for the year ending June 30, 1887. Serial Set volume 2565, session volume 1, 50th Congress, 1st Session, House Miscellaneous Document 86, page 221 (William A [sic] Cooper)
10 pension index, by name (William R Cooper)
11 pension index, by regiment, 91st PA Infantry, company K (William R Cooper)
12 company K, monthly report, April 1865 (Wm R Cooper)
[I did not find an entry for him in the index on <www.ancestry.com> to the pension index by name cards (searched April 2006)]