(1840 - 1876)
Home State: New York
Branch of Service: Infantry
Unit: Army of the Potomac
By August 1860, he was 2nd Lieutenant in the Battalion of St. Patrick, Papal Army in Italy. He was captured at Ancona in September and briefly a prisoner in Genoa, Italy before he was released. He was then in the Company of St. Patrick, a Vatican guard, in Rome, but resigned in March 1862.
He came to New York from Liverpool in April and was commissioned Captain and aide-de-camp (ADC), US Volunteers on 95 April 1862. He was with General Shields in the Valley of Virginia, then assigned to General McClellan.
On the Campaign
He was aide-de-camp to General McClellan on the Maryland Campaign of 1862.
The rest of the War
He was on General Buford's staff through 1863, notably at Gettysburg, PA in July, and was with the General at his death in December. He was promoted to Major and ADC on 7 April 1864 and was with General Stoneman to the end of the war. He was captured at Macon, GA in July, but was exchanged by September 1864. He was honored by brevet to Lieutenant Colonel on 13 March 1865 for his war service and mustered out of Volunteer service on 1 September 1866.
After the War
He was appointed 2nd Lieutenant in the 4th United States Cavalry on 4 May 1866 and Captain in the 7th US Cavalry on 28 July 1866. He was brevetted again, in March 1867, to Major and Lieutenant Colonel, USA (for Gettysburg and Dallas, GA). He was killed in action with Sioux and Cheyenne Indians at Little Big Horn on 25 June 1876, in command of Troop I, 7th US Cavalry. Originally buried on the field, he was reinterred in Auburn, NY in October 1877.
References & notes
His service from Heitman1 and Henry.2 His gravesite is on Findagrave. His picture from a group photograph of General John Buford and some of his staff, now at the Library of Congress.
More on the Web
Captain Keogh's horse from 1868, which he named Commanche, was said to be the only living thing found on the field at Little Big Horn after the battle. He died in 1891 and his preserved remains have since resided at Kansas University.
03/25/1840; Leighlinbridge, County Carlow, IRELAND
06/25/1876; Little Big Horn, MT; burial in Fort Hill Cemetery, Auburn, NY
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. 593 [AotW citation 28846]
2 Henry, Guy Vernor, Military Record of Civilian Appointments in the United States Army, 2 Volumes, New York: D. Van Nostrand, 1873, Vol. 1, pg. 164 [AotW citation 28847]