The 12th, from the state at large, was mustered in for three years at Concord, Aug. 28 to Sept. 25, 1862. The original members were mustered out June 21, 1865, at Richmond and Manchester, Va., and the recruits were transferred to the 2nd N. H. infantry the same day. There were 1,019 original members and 444 recruits, in all 1,463. Of these 180 were killed or died of wounds and 146 died from other causes. The 12th left "Camp Belknap" Sept. 27, 1862, for Washington, where it was assigned to the Army of the Potomac and was first under fire at Fredericksburg, Dec. 12-15, 1862. The regiment spent the winter at Falmouth, Va., and in May, 1863, was in the battle of Chancellorsville, where it suffered heavy losses. At Gettysburg its loss was again fearful. In the pursuit of Gen. Lee the regiment reached Warrenton, Va., when it was ordered to Point Lookout, Md., and was on duty there until the spring of 1864. In April it was assigned to the Army of the James and took part in the battles of Swift creek, Relay house, Drewry's bluff, and Port Walthall Junction. On June 1 it joined the Army of the Potomac at Cold Harbor and was actively engaged in that battle. Leaving Cold Harbor on the 11th, it reached Petersburg on the 15th, where it was constantly on duty until Aug. 25. The winter of 1864-65 was spent at Bermuda Hundred, Chaffin's farm, and in the vicinity of Fort Harrison. On the memorable Apr. 3, 1865, it entered Richmond and after a time spent at Danville, Va., was mustered out at Richmond.
The Regiment lost during service 11 Officers and 170 Enlisted men killed and mortally wounded and 1 Officer and 138 Enlisted men by disease. Total 320.
Cols., Joseph H. Potter, Thomas E. Barker; Lieut.-Cols., John F. Marsh, George D. Savage, Thomas E. Barker, Nathaniel Shackford; Majs., George D. Savage, John F. Langley, Nathaniel Shackford, Edwin E. Bedee.
Attached to Casey's Division, Military District of Washington, to December, 1862. 2nd Brigade, 3rd Division, 3rd Army Corps, Army of the Potomac, to June, 1863. 1st Brigade, 2nd Division, 3rd Army Corps, Army of the Potomac, to July, 1863. Marston's Command, Point Lookout, Md., District of St. Mary's to April, 1864. 2nd Brigade, 2d Division, 18th Army Corps, Dept. of Virginia and North Carolina, to December, 1864. 2nd Brigade, 3rd Division, 24th Army Corps, Dept. of Virginia, to June, 1865.
Duty in the Defences of Washington till October, 1862. Moved to Point of Rocks, Md., October 18; thence to Pleasant Valley October 19. Movement to Warrenton, Va., October 24-November 16, and to Falmouth November 18-24. Battle of Fredericksburg December 12-15. Burnside's 2nd Campaign ("Mud March") January 20-24, 1863. Duty at Falmouth till April. Chancellorsville Campaign April 27-May 6. Battle of Chancellorsville May 1-5. Gettysburg (Pa.) Campaign June 11-July 24. Battle of Gettysburg July 1-3. Ordered to Point Lookout, Md., July 26, and duty there guarding prisoners till April 7, 1864. Moved to Yorktown April 7, thence to Williamsburg. Butler's operations on south side of the James River and against Petersburg and Richmond May 4-28. Swift Creek (or Arrowfield Church) May 9-10. Operations against Fort Darling May 12-16. Battle of Drewry's Bluff May 14-16. Bermuda Hundred May 16-27. Moved to White House, thence to Cold Harbor, May 27-31. Battles about Cold Harbor June 1-12. Before Petersburg June 15-19. Siege of Petersburg and Richmond June 16, 1864, to April 2, 1865. Mine Explosion, Petersburg, July 30, 1864 (Reserve). Duty on the Bermuda Front August 26 to December, and in trenches before Richmond till April, 1865. Occupation of Richmond April 3. Guard and Provost duty at Manchester till June. Mustered out June 21, 1865.
The compiled service records of this unit contains 2155 men.
Dyer, Frederick H. - A Compendium of the War of the Rebellion