1st Company, Massachusetts Heavy Artillery
February 26, 1862 Organized for garrison duty in the forts of Boston Harbor, and on duty at Fort Warren
April, 1863 Assigned to 1st Battalion Heavy Artillery as Company A
2nd Company, Massachusetts Heavy Artillery
November 3, 1862 Organized for garrison duty in the forts of Boston Harbor, and on duty at Fort Warren
April, 1863 Assigned to 1st Battalion Heavy Artillery as Company B
3rd Company, Massachusetts Heavy Artillery
January 10, 1863 Organized for garrison duty in the forts of Boston Harbor.
March, 1864 Ordered to Washington, D.C. Attached to 2nd Brigade, De Russy’s Division, 22nd Corps, Dept. of Washington
July Attached to 3rd Brigade, DeRussy’s Division, 22nd Corps
August, 1864 Assigned to 3rd Heavy Artillery as Company A
4th Company, Massachusetts Heavy Artillery
April 22, 1863 Organized and assigned to 1st Battalion Heavy Artillery as Company C.
5th Company, Massachusetts Heavy Artillery
June 6, 1863 Organized and assigned to 1st Battalion Heavy Artillery as Company D
6th Company, Massachusetts Heavy Artillery
May 9, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C.. and garrison duty there. Attached to Third Brigade, Hardin’s Division, 22nd Army Corps
August, 1864 Assigned to 3rd Heavy Artillery as Company B
7th Company, Massachusetts Heavy Artillery
August 14, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty in the defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company C
8th Company, Massachusetts Heavy Artillery
August 14, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty there in the defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company D
9th Company, Massachusetts Heavy Artillery
August 27, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty in the Defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company E
10th Company, Massachusetts Heavy Artillery
September 16, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty in the Defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company F
11th Company, Massachusetts Heavy Artillery
October 20, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty in the Defenses of that cityattached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company G
12th Company, Massachusetts Heavy Artillery
November 20, 1863 Organized for garrison of forts in Boston Harbor. Ordered to Washington, D.C., and garrison duty in the Defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company H
13th Company, Massachusetts Heavy Artillery
February 10, 1864 Organized for garrison of forts in Boston Harbor.
March 7 Left Boston for Fortress Monroe, Va.
May Placed in charge of the pontoon train, Army of the James, and participated in the Campaign of Gen. Butler against Petersburg and Richmond, Va. Built and maintained bridges across the Appomattox, connecting Army of the Potomac and Army of the James, and the bridges acres James River used in the frequent crossings of the Federal armies during the siege of Petersburg.
August Assigned to 3rd Heavy Artillery as Company I, but remained detached.
April, 1865 In the Appomattox Campaign built the pontoon bridge a Farmville by which the 2nd and 6th Corps crossed in pursuit of Lee. and built the bridge at Richmond, Va. by which all the Union Armies crossed the James River on their way to Washington after close of the war.
September 26, 1865 Mustered out
14th Company, Massachusetts Heavy Artillery
May 12, 1864 Organized
June 23 Sailed from Gallop’s Island for Washington, D.C., and garrison duty in the Defenses of that city attached to 3rd Brigade, Hardin’s Division, 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company K.
15th Company, Massachusetts Heavy Artillery
May 20, 1864 Organized
June 23 Sailed from Gallop’s Island for Washington, D.C., and garrison duty in the Defenses of that city attached to 3rd Brigade, Hardin’s Division 22nd Army Corps, Dept. of Washington.
August, 1864 Assigned to 3rd Heavy Artillery as Company L
16th Company, Massachusetts Heavy Artillery
August, 1864 Organized
August Assigned to 3rd Heavy Artillery as Company M
September 22, 1864 Sailed for Washington, D.C.
17th – 28th Companies, Massachusetts Heavy Artillery
August, 1864 Organized
September 11-16 Left State for Washington, D.C.
November 12, 1864 Assigned to 4th Heavy Artillery
29th Company, Massachusetts Heavy Artillery
September 20, 1864 Organized
October 29 Ordered to Washington, and garrison duty in the Defenses of Washington, D.C.attached to 1st Brigade, DeRussy’s Division 22nd Army Corps.
June 16, 1865 Mustered out
30th Company, Massachusetts Heavy Artillery
September 1, 1864 Organized
September 26 Ordered to Washington. D.C. and garrison duty in the Defenses of that city attached to 1st Brigade, DeRussy’s Division, 22nd Army Corps
June 16, 1865 Mustered out