OVERVIEW:
Organized at Camp Brigham, Reedville, and duty there till December 25, 1861. Companies "A," "B," "C" and "D" left State for Annapolis, Md., December 25, 1861; thence moved to Hilton Head, S. C., February, 1862, and join Regiment. Second Battalion left State for New York December 27, and Third Battalion December 29 for same point; thence sailed for Hilton Head, S. C., January 13, arriving January 20, 1862. Attached to Department of the South to April, 1862. 3rd Brigade, 1st Division, Dept. of the South, to August, 1862. Companies "A" to "H" moved to Fort Monroe August 19, 1862; thence to Washington, D. C., and join Pleasanton's Cavalry, Army of the Potomac, at Tenallytown, September 3. Attached to Pleasanton's Cavalry, Army of the Potomac, to October, 1862. Averill's Brigade, Cavalry Division, Army of the Potomac, to January, 1863. 1st Brigade, 2nd Division, Cavalry Corps, Army of the Potomac, to April, 1865. (4 new Companies, "I," "K," "L," "M," organized December 5, 1863, to January 14, 1864.) Provost Marshal's Command, Army of the Potomac, to May, 1865. Headquarters, Army of the Potomac, to June, 1865.

SERVICE:
Duty at Hilton Head, S. C., till May, 1862. Moved to Edisto Island, S. C., May (Cos. "E" to "M"). Operations on James Island, S. C., June 1-28. Action James Island June 8. Battle of Secessionville June 16 (Co. "H"). Evacuation of James Island and movement to Hilton Head June 28-July 7. Poolesville, Md., September 4-5. Sugar Loaf Mountain September 10-11. South Mountain September 14. Battle of Antietam September 16-17. Shepherdstown, W. Va., September 19. Kearneysville, Shephardstown and Smithfield October 16-17. 4 Companies with 5th Corps October 30-November 25. 4 Companies near Hagerstown, Md., till November 16, thence moved to Washington November 16-25, and duty there refitting till December 13. Bloomfield November 2-3. Snicker's Gap November 3-4. Markham Station November 4. Manassas Gap November 5-6. Reconnoissance to Grove Church December 1. Battle of Fredericksburg, Va., December 12-15. Reconnoissance toward Warrenton December 21-23. Expedition to Richard's and Ellis' Fords December 29-30. Reconnissance to Catlett's and Rappahannock Station January 8-10, 1863. Elk Run, Auburn, January 9. Near Grove Church January 9. Destruction of Rappahannock Bridge February 5. Hartwood Church February 25. Kelly's Ford March 17. Bealeton March 17. Chancellorsville Campaign, Stoneman's Raid, April 29-May 6. Rapidan Station May 1. Near Prairie grove June 3. Kelly's Ford, Brandy Station and Stevensburg June 9. Aldie June 17. Upperville June 21. Battle of Gettysburg, Pa., July 2-3. Emmettsburg July 4. Williamsport July 6-7. Near Harper's Ferry, W. Va., July 14. Old Antietam Forge, near Leitersburg, July 10. Jones' Cross Roads July 12. Shepherdstown July 16. Near Aldie July 31. Scout to Hazel River August 4. Rixeyville August 5. Welford's Ford August 9. Scout to Barbee's Cross Roads August 24. Scout to Middleburg September 10-11. Advance from the Rappahannock to the Rapidan September 13-17. Culpeper C. H. September 13. Rapidan Station September 13-14-15. Bristoe Campaign October 9-22. Warrenton (or Rappahannock Station) October 12. Auburn and Bristoe October 14. Brentsville October 14. Picket near Warrenton till November 22. Mine Run Campaign November 26-December 2. Mine Run November 27. Scout and picket duty at Warrenton till April 21, 1864. Kilpatrick's Raid on Richmond February 28-March 4. Fortifications of Richmond March 1. (Cos. "C," "D" at Headquarters Army of the Potomac, April, 1864, to muster out.) Rapidan Campaign May-June. Todd's Tavern May 5-6. Wilderness May 6-7. Todd's Tavern May 7-8. Corbin's Bridge, Spottsylvania, May 8. Davenport Ford May 9. Sheridan's Raid to James River May 9-24. North Anna River May 9-10. Ground Squirrel Church, Ashland and Yellow Tavern May 11. Brooks' Church, or Richmond Fortifications, May 12. Line of the Pamunkey May 26-28. Totopotomoy May 28-31. Cold Harbor May 31-June 1. About Cold Harbor June 1-7. Sumner's Upper Bridge June 2. Sheridan's Trevillian Raid June 7-24. Trevillian Station June 11-12. Newark, or Mallory's Cross Roads, June 12. Black Creek, or Tunstall Station, and White House, or St. Peter's Church, June 21. St. Mary's Church June 24. Camp at Prince George Court House June 27-July 13. Weldon Railroad and Warwick Swamp July 12. At Lee's Mills till July 26. Demonstration on north side of James River July 27-29. Deep Bottom July 27-28. Malvern Hill July 28. Lee's Mills July 30. Scouting duty till August 14. Demonstration north of James River August 14-18. Gravel Hill August 14. Strawberry Plains August 14-18. Charles City Cross Roads August 18. Weldon Railroad August 19-21. Dinwiddie Road, near Ream's Station, August 23. Ream's Station August 25. Hawkinsville September 14. Jerusalem Plank Road September 16. Belcher's Mills September 17. Poplar Grove Church September 29-October 2. Davis' Farm September 30. Arthur's Swamp September 30-October 1. Vaughan Road October 1. (Old members left front for Massachusetts October 25, 1864.) Boydton Plank Road, Hatcher's Run, October 27-28. At McCann's Station till November 18. Reconnoissance toward Stony Creek November 7. At Westbrook House till December 1. Stony Creek Station December 1. Bellefield Raid December 7-12. Bellefield December 9-10. At Westbrook House till March 17, 1865. Dabney's Mills, Hatcher's Run, February 5-7. Provost duty at City Point till April 2. Fall of Petersburg April 2. Provost duty till May 27. Duty in the Defences of Washington till June 26. Mustered out June 29, 1865, and discharged at Readville, Mass., July 24, 1865.
3rd Battalion.-(Cos. "I," "K," "L" and "M.") Duty in District of Beaufort, S. C., till August, 1862. Action at Pocotaligo, S. C., May 22, 1862 (Detachment). Patrol and guard duty and picketing Broad River. Expedition to St. John s Bluff, Fla., September 30-October 13, 1862. Expedition to Pocotaligo, S. C., October 21-23. Pocotaligo Bridge October 21. Caston and Frampton's Plantation October 22. Attached to 10th Army Corps, Dept. of the South. Company "M" at Hilton Head, S. C., and outpost duty at Lawton's Plantation till August, 1863. A Detachment of Company "I" at Folly Island, S. C., till July, 1863, and Morris Island, S. C., to August, 1863. Balance of Company "I" on outpost duty at Hilton Head, S. C., June to August, 1863. Permanently detached from 1st Cavalry by S. C. 346, War Department, August 4, 1863, and designated Independent Battalion, Massachusetts Cavalry (which see).

Regiment lost during service 6 Officers and 93 Enlisted men killed and mortally wounded and 140 Enlisted men by disease. Total 239.