Battery D is referenced on a War Department marker at Antietam and honored by a monument at Gettysburg.

1861
June Attached to Wilcox’s Brigade, Heintzelman’s Division, McDowell’s Army of Northeast Virginia
July 16-21 Advance on Manassas, Va.
July 21
Battle of Bull Run
August Duty in the Defenses of Washington, D.C. attached to Kearney’s Brigade, Division of the Potomac
October Attached to Artillery, Franklin’s Division, Army of the Potomac
1862
March Attached to Artillery, 1st Division, 1st Army Corps, Army of the Potomac
March 10-15 Advance on Manassas, Va.
April 9-19 Advance to Falmouth, Va. Attached to Artillery, 1st Division, Department of the Rappahannock
April Moved to the Virginia Peninsula.
May to August Peninsula Campaign. Attached to Artillery, 1st Division, 6th Army Corps, Army of the Potomac
May 7 West Point
June 25-July 1 Seven days before Richmond
June 30
Glendale
July 1
Malvern Hill
July-August At Harrison’s Landing
August 16-24 Moved to Alexandria
September 6-22 Maryland Campaign
September 14 Crampton’s Pass, South Mountain, Md.
September 16-17
Battle of Antietam

The battery was commanded at Antietam by Captain Edward B. Williston. It lost 2 men killed.

From the marker along Smoketown Road on the Antietam battlefield:

Battery D, 2d U.S. Artillery, moved from its bivouac near Crampton’s Pass on the morning of the 17th and went into position south of the Smoketown Road, its center 55 yards from this point, its right gun about 12 yards. It opened fire at the Dunkard Church and the woods surrounding it to drive therefrom the Confederate Sharpshooters. It was relieved by Battery A, Maryland Light Artillery, Captain John W. Wolcott, and at 4 P.M., moved southwest to the high ground north of the Sunken Lane to cover the movement of the 7th Maine Infantry against the Confederates around the Piper buildings.

October 30-November 19 Movement to Falmouth, Va.
December 12-15
Battle of Fredericksburg
December-April At Falmouth
1863
April 27-May 6 Chancellorsville Campaign
April 29-May 2 Operations at Franklin’s Crossing
May 3 Battle of Maryes Heights, Fredericksburg
May 3-4
Salem Heights
May Attached to Artillery Brigade, 6th Army Corps
July 2-4
Battle of Gettysburg

Commanded by Lieut. Edward B. Wiliston, the battery brought four light 12 pounders to the field but remained on Taneytown Road and was not engaged.

July Attached to 1st Brigade, Horse Artillery, Army of the Potomac
September 13-17 Advance from the Rappahannock to the Rapidan
September 13 Culpeper Court House
September 14-16 Raccoon Ford
September 21-23 Reconnaissance across the Rapidan
October 9-22 Bristoe Campaign
October 10 Raccoon Ford and Morton’s Ford
October 11 Morton’s Ford, Stevensburg, and near Kelly’s Ford
October 11-12 Brandy Station or Fleetwood
October 15 Oak Hill
November 7-8 Advance to line of the Rappahannock
November 26-December 2 Mine Run Campaign
1864
May 4-June 12 Rapidan Campaign
May 5-7
Battle of the Wilderness
May 7-8 Todd’s Tavern
May 9-24 Sheridan’s Raid to the James River
May 11
Ground Squirrel Church and Yellow Tavern
May 26-28 On line of the Pamunkey
May 28 Haw’s Shop
May 28-31 Totopotomoy
June 1-7
Cold Harbor
June 7-24 Sheridan’s Trevillian Raid
June 11-12
Trevillian Station
June 21 Black Creek or Tunstall Station and White Horse or St. Peter’s Church
June 29-August 2 Siege of Petersburg
July 27-28 Deep Bottom
July 28 Malvern Hill
August 7-November 28 Sheridan’s Shenandoah Valley Campaign. Attached to Horse Artillery, Army of the Shenandoah, Middle Military Division
August 11 Tell Gate, near White Post, and near Newtown
August 25 Near Kearneysville
August 28 Leetown and Smithfield, W. Va.
August 29 Smithfield Crossing, Opequan
September 15 Sevier’s Ford, Opequan
September 19
Third Battle of Winchester (Opequan)
September 21
Fisher’s Hill
September 22 Milford
October 8-9 Tom’s Brook
October-December Duty at Winchester and in the Shenandoah Valley
December Duty at Pleasant Valley, Md. attached to Reserve Horse Artillery, Army of the Shenandoah
1865
April At Washington, D.C. attached to Horse Artillery, Defenses of Washington, D.C., 22nd Army Corps until October