See also: https://museum.dmna.ny.gov/unit-history/infantry/12th-regiment-new-york-national-guard

New York TWELFTH REGIMENT. (Three Months) This regiment was organized as the 11th Regiment by a general order dated June 21, 1847, and was of eight companies, viz.: Light Guard of 106th Regiment; Benson Guard, of 125th Regiment; Independence Guard, of 264th Regiment; Italian Guard, of 252d Regiment; Monroe Blues, of 235th Regiment; Tompkins Blues, of 51st Regiment; Independent Tompkins Blues, of 222d Regiment, and LaFayette Fusiliers of 85th Regiment. By a general order dated July 27, 1847, the designation of the regiment was changed to the 12th. A new company, under command of Capt. Henry Johnson, was organized and attached to the regiment, April 25, 1849. Company H of the 3d Regiment was transferred to the 12th Regiment, April 25, 1849. Company D was consolidated with Company C, June 5, 1849. A new company, under Capt. Adolphus I. Johnson, was organized April 15, 1850. Company L was transferred to the 11th Regiment, May 3, 1858. On March 16, 1859, Companies A and C, B and H, and G and E were consolidated, and the consolidated companies, with Company D, transferred to the 10th Regiment. On June 29, 1859, these transferred companies were disbanded. On November 16, 1859, five companies (A, B, C, D and G) were organized in the 22d Regimental District. On November 22, 1859, Company E was organized and an election ordered for field officers of the 22d Regiment. These companies were composed principally of former members of the old 12th Regiment. The designation of the 22d Regiment was changed December 19, 1859, to 12th Regiment. Company H was organized January 28, 1860, and Company F, February 2, 1860. Company C was consolidated with Company E, March 21, 1861, and Company K was organized May 8, 1861. Company I, 23d Regiment, was transferred to 12th Regiment, as Company I, April 2, 1861. New Company C was organized December 31, 1861. Company K was disbanded February 12, 1862, and new Company K organized September 22, 1862. Company C was consolidated with Company H, January 12, 1876. Company I was consolidated with Company G, January 12, 1876. New Company I, organized February 21, 1876. Company D was consolidated with Company E, March 11, 1876. New Company D was organized July 16, 1884, and new Company C was organized June 3, 1885. The regiment performed duty during the Astor Place riots in 1849; it was on duty during the Orange riots in July, 1871; during the Railroad riots in July, 1877; during the Switchmen's strike at Buffalo, in August, 1892, and at Brooklyn during the Motormen's strike in January, 1895. April 28, 1898, the regiment was authorized to be organized as a twelve company regiment to enter the United States service, in which it was mustered in as the 12th Regiment Infantry, N. Y. Volunteers, May 13, 1898, and mustered out April 20, 1899; Companies L and M were disbanded April 24, 1899. Service in the War of the Rebellion. April 21, 1861, the regiment, ten companies, commanded by Colonel Butterfield, left the State en route to Washington, D. C., where it was mustered in the United States service, for three months, May 2, 1861. It served at and near Washington from May, 1861, and in the Army, Department of Pennsylvania (General Patterson); and was mustered out at New York city, August 5, 1861. After the regiment's return from this service a large number of its members entered the volunteer service, for three years, in an organization known as the 12th Militia, which was, in January, 1862, consolidated with the 12th Volunteers. May 27, 1862, the regiment, nine companies then commanded by Col. William G. Ward, was again ordered to Washington, D. C., and left the State, June 6, 1862; it was mustered in the United States service for three months, served at Harper's Ferry, W. Va., in the 4th Brigade; volunteered to stay over its term of service, and was surrendered with Harper's Ferry; it was mustered out at New York city, October 8, 1862, and declared exchanged January 11, 1863. June 18, 1863, the regiment, ten companies, was ordered to Harrisburg, Pa., and it left the State, under Colonel Ward on the 20th; it was mustered in the service of the United States, for thirty days, served in General Yates' command at Fenwick, Pa., and in the 1st Brigade, Dana's Division, Department Susquehanna, and July 20, 1863, was mustered out of that service at New York city.

Source: The Union Army, vol. 2

New York TWELFTH REGIMENT. (Three Months) This regiment was organized as the 11th Regiment by a general order dated June 21, 1847, and was of eight companies, viz.: Light Guard of 106th Regiment; Benson Guard, of 125th Regiment; Independence Guard, of 264th Regiment; Italian Guard, of 252d Regiment; Monroe Blues, of 235th Regiment; Tompkins Blues, of 51st Regiment; Independent Tompkins Blues, of 222d Regiment, and LaFayette Fusiliers of 85th Regiment. By a general order dated July 27, 1847, the designation of the regiment was changed to the 12th. A new company, under command of Capt. Henry Johnson, was organized and attached to the regiment, April 25, 1849. Company H of the 3d Regiment was transferred to the 12th Regiment, April 25, 1849. Company D was consolidated with Company C, June 5, 1849. A new company, under Capt. Adolphus I. Johnson, was organized April 15, 1850. Company L was transferred to the 11th Regiment, May 3, 1858. On March 16, 1859, Companies A and C, B and H, and G and E were consolidated, and the consolidated companies, with Company D, transferred to the 10th Regiment. On June 29, 1859, these transferred companies were disbanded. On November 16, 1859, five companies (A, B, C, D and G) were organized in the 22d Regimental District. On November 22, 1859, Company E was organized and an election ordered for field officers of the 22d Regiment. These companies were composed principally of former members of the old 12th Regiment. The designation of the 22d Regiment was changed December 19, 1859, to 12th Regiment. Company H was organized January 28, 1860, and Company F, February 2, 1860. Company C was consolidated with Company E, March 21, 1861, and Company K was organized May 8, 1861. Company I, 23d Regiment, was transferred to 12th Regiment, as Company I, April 2, 1861. New Company C was organized December 31, 1861. Company K was disbanded February 12, 1862, and new Company K organized September 22, 1862. Company C was consolidated with Company H, January 12, 1876. Company I was consolidated with Company G, January 12, 1876. New Company I, organized February 21, 1876. Company D was consolidated with Company E, March 11, 1876. New Company D was organized July 16, 1884, and new Company C was organized June 3, 1885. The regiment performed duty during the Astor Place riots in 1849; it was on duty during the Orange riots in July, 1871; during the Railroad riots in July, 1877; during the Switchmen's strike at Buffalo, in August, 1892, and at Brooklyn during the Motormen's strike in January, 1895. April 28, 1898, the regiment was authorized to be organized as a twelve company regiment to enter the United States service, in which it was mustered in as the 12th Regiment Infantry, N. Y. Volunteers, May 13, 1898, and mustered out April 20, 1899; Companies L and M were disbanded April 24, 1899. Service in the War of the Rebellion. April 21, 1861, the regiment, ten companies, commanded by Colonel Butterfield, left the State en route to Washington, D. C., where it was mustered in the United States service, for three months, May 2, 1861. It served at and near Washington from May, 1861, and in the Army, Department of Pennsylvania (General Patterson); and was mustered out at New York city, August 5, 1861. After the regiment's return from this service a large number of its members entered the volunteer service, for three years, in an organization known as the 12th Militia, which was, in January, 1862, consolidated with the 12th Volunteers. May 27, 1862, the regiment, nine companies then commanded by Col. William G. Ward, was again ordered to Washington, D. C., and left the State, June 6, 1862; it was mustered in the United States service for three months, served at Harper's Ferry, W. Va., in the 4th Brigade; volunteered to stay over its term of service, and was surrendered with Harper's Ferry; it was mustered out at New York city, October 8, 1862, and declared exchanged January 11, 1863. June 18, 1863, the regiment, ten companies, was ordered to Harrisburg, Pa., and it left the State, under Colonel Ward on the 20th; it was mustered in the service of the United States, for thirty days, served in General Yates' command at Fenwick, Pa., and in the 1st Brigade, Dana's Division, Department Susquehanna, and July 20, 1863, was mustered out of that service at New York city.

Source: The Union Army, vol. 2

New York 12th Infantry National Guard State Guard (Union)

5/2/61

Organized - New York 12th Infantry National Guard State Guard - New York

7/20/63

Mustered Out - New York 12th Infantry National Guard State Guard - New York

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