Lt. Colonel Beaver was promoted to colonel of the 148th Pennsylvania Infantry Regiment. Major Curtin was promoted to lieutenant colonel.

Battle of South Mountain

The regiment was commanded by Lt. Colonel Curtin while Colonel Welsh commanded the brigade. It lost 145 casualties. Lieutenants James Cole and George Smith were killed, Lieutenant William Grove was mortally wounded, Lt. Colonel Curtin was lightly wounded in the arm but remained in command, and Captain Theodore Gregg was wounded.

Battle of Antietam

The regiment lost 1 killed, 36 wounded and 1 missing

From the regimental monument on Branch Avenue at Antietam:

The Regiment advanced 264 yards Northwest of this point, retiring to this position later in the day.

From the War Department tablet for Welsh’s Brigade on the Antietam battlefield:

On the morning of the 17th Welsh’s Brigade was in reserve on the eastern slope of the ridge on the left bank of the Antietam, nearly opposite the Burnside Bridge. About 2 P.M., after Sturgis’ Division had carried the bridge, the Brigade crossed and, following the road to Sharpsburg about 250 yards, formed line west of the road.

The Brigade then advanced over the high ground west of the road, gradually crossing to the east, until its right was near this point, its center in the ravine and at the stone mill, and its left in the apple orchard beyond, when the attack of A.P. Hill on the left flank of the Corps compelled it to withdraw to the banks of the Antietam, where it remained until the evening of the 18th.

Battle of Fredericksburg

The regiment was in reserve and suffered no casualties

Siege of Jackson

Captain William Chase wounded

Blue Springs

The regiment lost 21 casualties, including Captain R. Chessman, who was wounded

Lenoir Station

Captain Hart with a wagon train and 16 men were captured

Siege of Knoxville

Battle of the Wilderness

The regiment lost 145 casualties. Lieutenant Evan R. Goodfellow was killed, Captain John Campbell mortally wounded, and Captains William Chase and Andrew Fessler and Lieutenant Cyrus Bruner wounded

Battle of Spotsylvania Court House

Lieutenant John Irvin was wounded.

Corporal John Kinsey of Company B earned the Medal of Honor for siezing the regiment’s colors from the wounded color bearer and saving them from capture “with great gallantry.”

Battle of Cold Harbor

The regiment lost 163 casualties in three days of fighting out of 300 effectives. Lieutenants De Witt Hoig and George Scudder were killed, Major Kelsey was mortally wounded and Lieutenants John Gelbaugh and John Rogers were wounded.

The regiment lost 3 killed and 18 wounded. Captain Chessman and Lieutenant Harvey Benner were wounded and Colonel Curtin was badly wounded in the shoulder and carried from the field.

Mine Explosion, Petersburg

The regiment fought in the crater, bringing 210 men under Captain Theodore Gregg. It lost 6 killed and 22 wounded, with 39 men missing. Captain Edgar Eyde and Lieutenants Adolph Campbell and Ephraim Jeffers were wounded and Captain Rees Richards captured

Corporal Franklin Hogan of Company A earned the Medal of Honor for capturing the colors of the 6th Virginia Infantry.

October 2

Poplar Springs Church

The brigade was surrounded, and Lt. Colonel Gregg unsuccessfully tried to cut the regiment through to Union lines. Lieutenant James Gregg was killed, Captain Andrew Fessler wounded and captured, and Lt. Colonel Gregg and Captain John Trout captured along with the balance of the regiment, some 150 men.

Peeble’s Farm

There were only 92 survivors of the regiment.

Assault on and fall of Petersburg

Lieutenant Levi Robb was mortally wounded. Captains Chessman, commanding the regiment, and Lafayette Lord were wounded.