Company "A" organized as 1st Company New Hampshire Heavy Artillery and mustered in July 22, 1863. Stationed at Fort Constitution until May 6, 1864. Company "B" organized as 2nd Company New Hampshire Heavy Artillery and mustered in September 17, 1863. Stationed at Fort McClary, Kittery Point, until May 6, 1864. These 2 Companies ordered to Washington, D.C., May 6, 1864. Attached to Augur's Command, Defenses of Washington, 22nd Corps, and assigned to duty in the Defenses of Washington, D.C. Company "A" at Forts Slocum, Stevens, Totten, Sumner and Batteries Cameron, Parrott, Kendall and Vermont until November, 1864. Ordered to Portsmouth Harbor November 25, 1864. Company "B" at Forts Bunker Hill, Saratoga, Lincoln, Bayard, Gaines and Foote until February, 1865, when ordered to Portsmouth Harbor, N.H. Repulse of Early's attack on Washington July 11-12, 1864 (Cos. "A" and "B"). Companies "C," "D," "E," "F," "G," "H," "I," "K" and "L" organized from September 2 to October 17, 1864. Company "M" formed by assignment of 1st New Hampshire Battery, Volunteer Light Artillery, November 5, 1864, but remained detached as a Light Battery. Each Company ordered to Washington, D.C., as fast as organized, and duty in the Defenses of that city until June, 1865. Regiment mustered out June 15, 1865. Recruits consolidated to 2 Companies and mustered out September 11, 1865.
