The 15th New York Heavy Artillery Regiment lost 8 officers and 142 enlisted men killed or mortally wounded and 5 officers and 225 enlisted men to disease during the Civil War.

1861
October – December Originally organized as 3rd Battalion German Heavy Artillery at New York City
December 19 Left State for Washington, D.C.
December-March Duty in the Defenses of Washington, D.C.
1862
March Attached to Artillery Brigade, Military District of Washington
May Attached to Whipple’s Command, Military District of Washington
July Attached to Fort Lyon, Defenses of Washington

1863

February Attached to Tyler’s Command, De Russy’s Division, 22nd Army Corps, Dept. of Washington
June Attached to 2nd Brigade, DeRussy’s Division, 22nd Army Corps
September 30 Designation of Regiment changed to 15th New York Heavy Artillery. 3rd Battalion assigned as Companies A – E.
October Attached to 4th Brigade, De Russy’s Division, 22nd Army Corps
1864
February Attached to Artillery Reserve, Army of the Potomac
March Attached to 1st Brigade, Artillery Reserve, Army of the Potomac
May-June Campaign from the Rapidan to the James. Attached to Kitching’s Independent Brigade, 5th Army Corps
May 5-7 Battle of the Wilderness
May 8-21 Spotsylvania Court House
May 19 Harris Farm (or Fredericksburg Road)
May 23-26 North Anna River
May 23 Jericho Mills
May 26-28 On line of the Pamunkey
May 28-31 Totopotomy
May 30 Attached to 1st Brigade, 3rd Division, 5th Army Corps
June 1-12 Cold Harbor
June 1-3 Bethesda Church
June 2 Attached to 3rd Brigade, 2nd Division, 5th Army Corps Company F attached to Artillery Reserve, Army of the Potomac to December
June 16-18 Before Petersburg
June 16 – April 2 Siege of Petersburg
June 22-23 Weldon Railroad
July 30 Mine Explosion, Petersburg (Reserve)
August Attached to 1st Brigade, 2nd Division, 5th Army Corps
August 18-21 Six-Mile House, Weldon Railroad
September 29-
October 2
Poplar Springs Church, Peeble’s Farm
October 27-28 Boydton Plank Road, Hatcher’s Run
1865
January Company M to Artillery Brigade, 5th Army Corps until June
February 5-7 Dabney’s Mills, Hatcher’s Run
March 28-April 9 Appomattox Campaign
March 29 Gravelly Run
March 31 Boydton Road and White Oak Road
April 1 Five Forks
April 2 Fall of Petersburg
April 3-9 Pursuit of Lee
April 9
Appomattox Court House

Surrender of Lee and his army.

May March to Washington, D.C. Attached to 4th Brigade, DeRussy’s Division, 22nd Army Corps
May 23 Grand Review
June Duty at Washington attached to 1st Brigade, DeRussy’s Division, 22nd Army Corps
August 22 Mustered out