He was born in 1842/43 (2 (18 in 1861)).
He enlisted and was mustered into service, at Philadelphia, Pennsylvania, on 20 August 1861 (1, 2) He was mustered in as a private, in company C (1, 2, 5).
He was not on the muster-out roll when the regiment mustered out (1). He was a private, in company C (5).
On 29 November 1906, Minnie S Liveright, daughter of Simon and Pauline Sternberger, died (3). If this is the Simon who served in the 91st, he died before she died (3).
On the other hand, a Samuel Simon Sternberger, husband of Pauline G., died at Atlantic City in June 1919 (4).
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) (Simon Steinberger)
2 Civil War Veterans' Card File, available at the Pennsylvania State Archives, searched 15 July 2004 (Simon Steinberger; rolls have 'Sternberger')
3 death notice, Minnie S Liveright, Philadelphia Inquirer, 30 November 1906, page 7
4 death notice, Philadelphia Inquirer, 28 June 1919, page 17 (Samuel Simon Sternberger)
5 index to compiled service records of volunteer Union soldiers who served in organizations from the state of Pennsylvania (Simon Sternberger)
STERNBERGER.--SAMUEL SIMON, husband of Pauline G. Sternberger, aged 75, at Marburg Apartments, Atlantic City, N.J. Relatives and friends, also Atlantic City Lodge, No. 276, B.P. of R.; Pequod Tribe, No. 47, I.O.R.M., are invited to attend funeral services, Sun. 9 A.M., at the parlors of Mrs. James Gormley, 1619 Pacific ave., Atlantic City, N.J., and at 11.30 A.M., at the Chapel of Mt. Sinai Cem., Phila.
LIVERIGHT.--On November 29, 1906, MINNIE S., wife of Louis F Liveright and daughter of Pauline and the late Simon Sternberger. Funeral from 43 East 60th st, New York, December 2, at 11 o'clock.