Bates (1) lists two George F Stroup's, in two different companies. Since one was not on the muster-out roll, I am assuming that they are the same person. The Pennsylvania State Archives card confirms this (6).
He was born in Philadelphia, Pennsylvania (7, 8). He was 26 years old when he was enlisted (6 [28], 7 [26], 8 [28 in 1863]).
He was a bootfitter (6, 7, 8).
He was 5 feet 6-1/2 inches tall, and had a dark complexion, dark eyes, and dark hair (6 [5'7", light complexion, hazel eyes, dark hair], 7 [5'6-1/2", dark complexion, dark eyes, dark hair], 8 [5'6-1/2", dark, dark, dark]).
He was enlisted and mustered into service on 7 January 1862 (1, 6, 7). He was enlisted for three years, at Philadelphia, Pennsylvania, by Lieutenant Weeks (6, 7). He was mustered in as a private, at Philadelphia, Pennsylvania (6). He initially served as a private in company B (1).
At some point, he was transferred to company F (6).
He was reported missing in action on 7 May 1863 (4, 7 [from 3 May]).
He was at Camp Convalescent, Alexandria, Virginia, on 8 September 1863, when Lieutenant Colonel Sinex asked for his return (2).
On 23 October 1863, he was reported regained from missing in action (5).
He reenlisted as a veteran volunteer on 26 or 30 March 1864 (1, 6, 8). He was enlisted for three years, at Warrenton Junction, Virginia, by Lieutenant Shipley (8).
He was wounded on 14 May 1864 at Spottsylvania Court House, Virginia (1, 10).
On 14 August 1864, he returned to the regiment from hospital (9).
On 14 March 1865, he was detailed for duty in the provost guard at the 3rd brigade headquarters (3).
He mustered out on 10 July 1865 with his company (1, 6).
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, Sinex to Marvin, 8 September 1863
3 special order 27, HQ 91st PA, 14 March 1865 (George F Stroup [could possibly be Shoup])
4 consolidated morning report, 91st PA, 7 May 1863 (Private Stroup)
5 consolidated morning report, 91st PA, 23 October 1863 (Pri Geo Stroup)
6 Civil War Veterans' Card File, available at the Pennsylvania State Archives, searched 29 June 2004 (George F Stroup)
7 company F, descriptive roll, #97 (George Felix Stroup)
8 company F, second descriptive roll, #21 (George F Stroup)
9 consolidated morning report, 91st Pennsylvania, 14 August 1864 (Private Geo Stroup)
10 'The Ninety-first Pennsylvania volunteers', Philadelphia Inquirer 8 June 1864 page 3 (Geo F Stroup)
[I did not find an entry for him in the index on <www.ancestry.com> to the pension index by name (searched April 2007)