See also: https://museum.dmna.ny.gov/unit-history/infantry/25th-regiment-new-york-national-guard

New York TWENTY-FIFTH REGIMENT. This regiment, then located at Albany, now not in existence, was ordered April 9, 1861, to proceed to Washington, D.C. Nine companies left the State April 27, 1861, and the tenth company (Company A), May 1, 1861. Companies A and R were known, respectively, as the Albany Republican artillery and the Burgesses Corps. The regiment, commanded by Col. Michael K. Bryan, served at and near Washington, where it was mustered in the United States service for three months. It was mustered out at Albany, August 4, 1861. June 5, 1862, the regiment (six companies), commanded by Colonel Bryan, again left the State, having been mustered in the United States service for three months, at Albany, May 31, 1862. It served at Suffolk, Va., in the 7th Corps, and was mustered out at Albany, September 8, 1862. The regiment lost by death in its service in 1861, of disease, three enlisted men; in 1862, drowned, one enlisted man; total, four. And it took part in the advance into Virginia and occupation of Arlington Heights, May 24, 1861.

Source: The Union Army, vol. 2

New York TWENTY-FIFTH REGIMENT. This regiment, then located at Albany, now not in existence, was ordered April 9, 1861, to proceed to Washington, D.C. Nine companies left the State April 27, 1861, and the tenth company (Company A), May 1, 1861. Companies A and R were known, respectively, as the Albany Republican artillery and the Burgesses Corps. The regiment, commanded by Col. Michael K. Bryan, served at and near Washington, where it was mustered in the United States service for three months. It was mustered out at Albany, August 4, 1861. June 5, 1862, the regiment (six companies), commanded by Colonel Bryan, again left the State, having been mustered in the United States service for three months, at Albany, May 31, 1862. It served at Suffolk, Va., in the 7th Corps, and was mustered out at Albany, September 8, 1862. The regiment lost by death in its service in 1861, of disease, three enlisted men; in 1862, drowned, one enlisted man; total, four. And it took part in the advance into Virginia and occupation of Arlington Heights, May 24, 1861.

Source: The Union Army, vol. 2

New York 25th Infantry National Guard State Guard (Union)

4/27/61

Organized - New York 25th Infantry National Guard State Guard - New York

9/8/62

Mustered Out - New York 25th Infantry National Guard State Guard - New York

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