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Federal Battery

Pennsylvania Light Artillery, Independent Battery C

"Thompson's Battery"
Organized: Pittsburgh, PA; mustered in 11/06/1861
Disbanded/Mustered out: Pittsburgh, PA 06/30/1865


Commanding Officer at Antietam:
  Capt. James Thompson


  4   3-in. Ordnance Rifle


This Battery's Chain of Command:
  Army - Army of the Potomac
  Corps - First (I) Army Corps
  Division - 2nd Division, I Corps
  Brigade - 2nd Division, I Corps Artillery

Unit history

Recruited and organized in Pittsburgh, mustering for three years service on 6 November 1861, initially with Captain James Thompson, and Lieutenants John P. Barry and James Stephenson. They were with McDowell's Corps in the defenses of Washington, and on the 2nd Bull Run Campaign. This battery was composed of men from Pennsylvania and Maryland, and was originally identified as the 2nd Maryland Battery, but Thompson argued for, and had that changed by the Spring of 1862, to Thompson's Independent Pennsylvania Battery (Officially renamed by the state as Independent Battery "C" in May 1863).

On the Antietam Campaign

"At the close of the campaign, the battery retired to Washington, and was immediately put upon the march through Maryland, to meet the enemy, who had crossed the Potomac, receiving four ten-pound rifled guns from the Second Maine, at Rockville, while on the march. In the battle at South Mountain, on the 14th, it was engaged, but sustained no loss. On the morning of the 17th of September, the battery was brought into position upon the field at Antietam, and went into action upon the right of the line, with Duryea's Brigade, replying to a rebel battery upon the right front. Finding that a battery upon the left had gotten the exact range of his guns, Captain Thompson turned his fire upon it."

" 'Immediately afterwards,' says Captain Thompson, in his official report, 'I was ordered to advance, when I selected a little knoll in the centre of a corn-field, and coming into action, I observed the enemy's infantry advancing from the woods to our right. I at once directed my fire on them, using three, two, and one and a-half second fuse as they advanced, but was unable to use canister, as many of our men retiring, wounded, got in front of my guns. Finding at length, the remnants of the brigade retiring their ammunition exhausted-and the enemy already in the corn-field, within seventy-five yards of the battery, I retired to the rising ground in the centre of the grass-field, about two hundred yards in rear, and continued my fire. But finding that all of our division had gone, and that my men and horses were falling fast, I limbered up and moved off, just as fresh troops coming up, obliqued across the front of the battery into position for our relief.' "

"One gun had to be abandoned for a few moments, on account of the loss of horses, until other horses could return for it, when guns and limbers were brought off in safety. The loss was eleven men wounded, one mortally, and thirteen horses killed."1

Map Showing this Unit

Battlefield Tablets for this Unit

Tablet #1: First Army Corps - 16 Sep, 2 PM to 16 Sep, 6 PM
Tablet #14: Ricketts' Division, First Army Corps - 16 Sep, 2 PM to 16 Sep, 8 PM
Tablet #120: Army of the Potomac - 17 Sep, 5 AM to 17 Sep, 12 PM
Tablet #7: Ricketts' Division, First Army Corps - 17 Sep, 6 AM to 17 Sep, 5 PM
Tablet #8: Duryea's Brigade, Ricketts' Division - 17 Sep, 6 AM to 17 Sep, 8 AM
Tablet #81: Ricketts' Division, First Army Corps - 17 Sep, 6 AM to 17 Sep, 9 AM

After the Antietam Campaign

They were at Fredericksburg in December, and on the Chancellorsville Campaign in 1863. In June the surviving remnants of Captain Hampton's Battery F (PA Lt.) was combined with Battery C, under Captain Thompson. They were in combat at Gettysburg and in the Virginia actions of late 1863 - early 1864. In April 1864 sufficient recruits had been received to split back into two batteries - Battery F being reconstituted. Battery C served the remainder of the War in the defences of Washington.

References & Notes

See an excellent, detailed history of the unit from Gary V. Hoover. Additional unit history data from Dyer's 2

We have 6 individuals in the AotW database for this unit:


Co. Rank Name Casualty? Details*
UnkCorpDennison, William WIA   09/17     We have some details for this person
UnkPvtSullivan, John WIA   09/17     We have some details for this person
UnkCorpSweesy, John J.WIA   09/17     We have some details for this person
--PvtAuday, David L.WIA   09/17
--PvtHenderson, Thomas MWIA   09/17     We have some details for this person
--CaptThompson, James         We have some details for this person


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1   Bates, Samuel Penniman, History of the Pennsylvania Volunteers, 1861-65, Harrisburg: State of Pennsylvania, 1868-1871  [AotW citation 81]

2   Dyer, Frederick H., A Compendium of the War of the Rebellion, Des Moines, Iowa: The Dyer Publishing Co., 1908, Independent Battery C, PA Artillery  [AotW citation 82]