Organized at Harrisburg at Camp Curtin

• Company A – “The Wayne Guards” – Philadelphia – Captain Henry B. Whisner
• Company B – “The Factoryville Infantry” – Wyoming County – Captain David N. Matthewson
• Company C – “The Troy Guards” – Bradford County – Captain Richard Gurtin
• Company D – “The Kepner Fencibles” – Dauphin Countin – Captain Samuel B. Wilt
• Company E – “The Easton Guards” – Northampton County – Captain Peter Baldy
• Company F – “The West Newtown Guards” – Westmoreland County – Captain Andrew G. Oliver
• Company G – “The Bailey’s Invincibles” – York County – Captain Samuel N. Bailey
• Company H – “The Indiana County Infantry” – “Indiana County” – Captain Andrew J. Bolar
• Company I – “The Huntingdon Guards” – Huntingdon County – Captain James C. Baker
• Company K = “The McClure Rifles” – Franklin County – Captain John S. Eyster

Action at Dranesville

The regiment lost one man wounded.

Seven days before Richmond

Battles of Mechanicsville

For six hours defended a line of rifle pits behind Beaver Dam Creek supported by a section of Cooper’s Battery, expending over a hundred rounds per man. The regiment held its position until daylight, when it was ordered to retire, which it successfully did under fire.

Battle of Gaines’ Mill

Marched to Gaines’ Mill and moved to the support of Griffin’s Battery, defending the guns until dusk Losses were six killed and 25 wounded, including Miles M. Cooper and Newton Ford of Company C, both mortally wounded by a single shell. The regiment was then ordered to cross the Chickahominy.

Charles City Cross Roads

Guarded the Reserve Artillery in an 18 mile march, the regiment “suffering greatly from fatigue and lack of water.”

Glendale

The regiment was placed in an awkward position on the extreme left of the Union line, divided into three scattered parts. After intense fighting that became hand to hand at times, they were enfiladed and withdrew. The regiment rallied, though, and returned to the fighting until it died down at the end of light.

Losses were six killed, including First Lieutenant William W. Arnold of Company G; 36 wounded, including Captains Franklin Daniels of Company A and Thomas D. Horn of Company D; and 23 missing, including First Lieutenant Henry S. Lucas of Company C, who was captured.

Malvern Hill

In reserve in front of the Malvern Mansion.

Battles of Gainesville 

The regiment lost several men killed and wounded from artillery fire while marching and countermarching.

Battles of Groveton (Brawner’s Farm)

Second Battle of Bull Run (Second Manassas)

Colonel Hardin was severly wounded in severe fighting near Henry House. Captain Gustin took command of the regiment, which lost a total of five killed and 38 wounded.

Maryland Campaign

Attached to 3rd Brigade, 3rd Division, 1st Corps, Army of the Potomac

Battle of South Mountain

Assaulted Turner’s Gap, losing six killed and 19 wounded.

Battle of Antietam

Captain Gustin continued to command the regiment, which was part of Anderson’s Brigade.

From the first War Department tablet for the brigade at Antietam:

Anderson’s Brigade of Meade’s Division bivouacked in this low field on the night of September 16, 1862.

Its outposts were established in the south edge of the wood in front and beyond the Hagerstown Pike to the west.

From the second War Department tablet for the brigade at Antietam:

Anderson’s Brigade advanced from the North Woods about 6:30 A.M. in support of Doubleday’s Division engaged on either side of the road south of this point. Midway between the North Woods and D. R. Miller’s, the 10th Regiment crossed the road and moving west about 700 yards became engaged with the enemy’s skirmishers and the Artillery of Stuart’s Cavalry Command. The three remaining Regiments formed line with the right resting on the road at this point. A charge of the enemy to the north edge of the Cornfield was repulsed and the Brigade advanced to the Cornfield, the 9th Regiment going through the corn to its south edge, the center and left about midway into the corn, when it was checked by the advance of a Confederate line and fell back, after which Anderson withdrew to the North Woods, where he was rejoined by the 10th Regiment and served as a rallying point for Sedgwick’s Division, Second Corps. The Brigade then moved to the rear of the high ground north of Joseph Poffenberger’s.

From the third War Department tablet for the brigade at Antietam:

Anderson’s Brigade advanced from this point about 6:30 A.M. in support of Gibbon’s, Phelps’ and Patrick’s Brigades of Doubleday’s Division, midway between the North Woods and the D. R. Miller house, the 10th Regiment was sent to the west about 700 yards to protect the flank of the Union line against a threatened advance of the enemy. The three remaining Regiments became engaged with the enemy in the north edge of the Cornfield south of the Miller house.

The regiment lost 13 killed, 47 wounded and 4 missing.

Battle of Fredericksburg

The regiment was part of Meade’s attack which broke Jackson’s line, but was forced to withdraw when other Union assaults failed. The regiment suffered 13 killed, 70 wounded, and 34 prisoners. Lieutenant Franklin Stephens was wounded and Captain Andrew Bolar was shot through both legs and captured. Lieutenant Kern was stunned senseless by a cannon ball that struck the ground in front of him and shredded his cap, but he recovered.

Battle of Gettysburg

The 12th Pennsylvania Reserves was commanded by Colonel Martin D. Hardin. The regiment advanced from behind Little Round Top to the summit of Big Round Top in line of battle with the 20th Maine. The regiment’s losses were on July 3rd to sharpshooters.

From the monument to the 9th Reserves on Big Round Top at Gettysburg:

Occupied this position (Big Round Top) on the evening of July 2nd and held it to the close of the battle.

Present at Gettysburg 26 Officers and 294 men. Killed 1 man, wounded 1 man.

Bristoe Campaign

Rappahannock Station

Mine Run Campaign

Rapidan Campaign

Colonel Martin Hardin recovered from his wound to take command of the brigade, while Lieutenant Colonel Richard Gustin remained in command of the regiment.

Battles of the Wilderness

“Hotly engaged,” but with light losses.

Laurel Hill

Battle of Spotsylvania Court House

Assault on the Salient

Battle of Harris Farm

North Anna River

Bethesda Church