(1819 - 1885)
Home State: Massachusetts
Education: Harvard (1838), USMA, Class of 1842;Class Rank: 1/56
Command Billet: Commanding Regiment
Branch of Service: Infantry
He was the youngest of the seven sons of Colonel Abraham Eustis (1786-1843) of the First US Artillery. After Harvard he attended the US Military Academy at West Point and graduated first in his class in July 1842. He was commissioned 2nd Lieutenant of Engineers and served on construction projects in New England to 1847 and then was Assistant Professor of Engineering at West Point. He resigned from the Army on 30 November 1849.
He was an engineering professor at Harvard from December 1849 until 15 August 1862 when he accepted a commission from the Governor as Colonel of the 10th Massachusetts Infantry.
On the Campaign
He commanded the regiment in Maryland. They were in Pleasant Valley on 16 September, marched nearly to Harpers Ferry and back to Keedysville on the 17th, and arrived on the battlefield of Antietam about 11 a.m. on 18 September 1862.
The rest of the War
He was in action with the regiment at Fredericksburg, then led the brigade (by then in the 3rd Division, Sixth Corps) at Salem, VA and on the Gettysburg, PA Campaign of 1863. He was appointed Brigadier General of Volunteers on 12 September 1863 and was on active operations until May 1864 at Spotsylvania Court House, VA, where he was thought to be drunk and was relieved of his command. He returned to briefly command another brigade but was forced to resign his commission on 27 June 1864. He was reported to be a user of opium, although that may have been by prescription for an unknown health condition which had long plagued him.
After the War
He returned to his chair at Harvard, was appointed Dean of the Lawrence Scientific School (1871), and taught there until his death at about age 66 in 1885, of lung and liver diseases.
References & notes
His service from Heitman1 and Cullum2. His Cullum Number is 1111. Personal details from his obituary in the Harvard Crimson of 13 January 1885, and from family genealogies, including his own Genealogy of the Eustis Family (1878). His gravesite is on Findagrave. His picture from a CDV sold on ebay.
He married Sarah Augusta Eckley (1823-1853) in May 1844 and they had 3 sons and a daughter by 1853. He married again, Caroline Bartlett Hall (1825-1916) in July 1856, and they had two more sons.
More on the Web
There's a superb post-war photograph of him online from the Harvard School of Engineering and Applied Sciences, and a later photograph of him from the Harvard Book (1875).
He's one of 11 Union Generals buried at Mt. Auburn [pdf].
See an interesting side-story about his brother Frederic Augustus (1816-1871) who ran their late step-mother's large plantation on Lady's Island, South Carolina during and after the War (thanks to research by Cowan's Auctions on a slave record of the period). A related photograph is online from the University of North Carolina.
02/01/1819; Fort Independence (Boston Harbor), MA
01/11/1885; Cambridge, MA; burial in Mount Auburn Cemetery, Cambridge, MA
1 Heitman, Francis Bernard, Historical Register and Dictionary of the United States Army 1789-1903, 2 volumes, Washington DC: US Government Printing Office, 1903, Vol. 1, pg. 408 [AotW citation 26139]
2 Cullum, George Washington, Biographical Register of the Officers and Graduates of the US Military Academy, 2nd Edition, 3 vols., New York: D. Van Nostrand, 1868-79, Vol. II, pp. 109-110 [AotW citation 26140]