1.  Photograph of Capt. William S. Stroub from William Kepler's book, 4th Ohio Volunteers:  Gibraltar Brigade, Army of the Potomac (1886, Cleveland, OH; reprinted 1992, Blue Acorn Press, P.O.B. 2684, Huntington, WV 25726). 

1a.  Allen L. Potts.  Marion County, Ohio, Probate Court Marriage Records, Vols. I-XII, 1824-1902 (online at Heritage Pursuit):

Stroub, William S.

Young, Elizabeth J.

7/31/1864

J.J. Idleman

1b.  Jordan R. Dodd, ed.  1998.  Marriage Index: Ohio, 1851-1900.  Liahona Research, Orem, UT (Broderbund CD-236):  there are no Elizabeth STRAUB marriages on the CD, so it appears Elizabeth may not have remarried. 

2.  1870 Census Images (online at Ancestry.com; Image #3 of 7):  Waldo P.O., Village of Waldo, Marion Co., OH, p. 211A, PN 3, enumerated 7 Jun 1870, official enumeration date 1 Jun 1870 (extracted by Diana Gale Matthiesen).  For full record, see Thomas RENZENBERGER's family group sheet. 

22	23	Renzenberger Thomas	36	M	W	Carpenter	400	100	Pennsylvania
		[Thomas's wife, children, et al.]
	24	Young Malinda	74	F	W	Keeping house			Maryland
		Stroub Elizabith	30	F	W	Milliner	400	1300	Ohio

Malinda is almost certainly Elizabeth's mother.

3.  Ohio Genealogical Society.  1991.  Index to the 1880 Federal Population Census for the State of Ohio.  (Broderbund  CD-20):  there is no Elizabeth STRAUB (or var.) in Marion Co.

4.  Paul J. & Barbara Midlam.  1985.  Marion County, Ohio, Cemetery Inscriptions (online at Heritage Pursuit):

STRAUB, William S.

(Capt) Co. H 4th OVI d Mar 27 1866 Aged: 27y

Waldo [Cemetery]

Waldo

5.  Anon.  Tuesday, 30 May 1893.  "The Steam Shovel's Dead."  Marion Daily Star, Marion, OH (online at Ancestry.com).  On p. 7?:

THE STEAM SHOVEL'S DEAD. Floral Wreathes Are Placed on Their Graves as a Token of Memory.    The employes of the Marion Steam Shovel company have inaugurated a commendable custom.  It is decorating the graves of their dead with wreathes of flowers.    The Steam Shovel's dead now number nine and this forenoon, without display or parade, committees were sent out, and beautiful floral wreathes were tenderly laid on their graves in memory of the time when they were companions in the duties of their daily labor.    The following is a list of their dead:  H.M. Barnhart, Jacob Keiler, Wm. Straub, Benj. Oborn, John Dombaugh, Henry Knickle, William Vestal, Green Camp; Charles Watters, St. Mary's; Frank Rhoads, Cochranton.  The wreaths were sent to the last three places, and here, too, the sweet tokens of membory will be laid on their graves.

Is this our subject? 

6.  Anon.  1883.  History of Marion County, Ohio.  Leggett, Conaway, & Co., Chicago (online at HeritagePursuit.com). See excerpt for William S. STRAUB's participation in the Civil War. 

7.  Marion County Ohio Roll of Honor extracted from New Historical Atlas, Marion County, Ohio, Illustrated, 1878 (online at the Marion County OHGenWeb site).