Advance on Manassas, Virginia.

Pope’s Campaign in Northern Virginia

The 21st New York Infantry Regiment lost 3 officers and 50 men killed and 2 men wounded exclusive of Bull Run.

Groveton

Second Battle of Bull Run (Second Manassas)

Lost 2 officers and 35 men killed and 16 men wounded.

Battle of Chantilly

Formed the right of the line of battle.

Maryland Campaign

Battle of South Mountain

Engaged as skirmishers, losing 1 man killed and 1 wounded.

Battle of Antietam (Sharpsburg)

Fought on the right of the line, losing 12 men killed, 6 men mortally wounded, and 2 officers and 49 enlisted men wounded.

There are three markers for Patrick’s Brigade on the Antietam battlefield.

From the first marker is on the east side of Mansfield Avenue near Hagerstown Pike:

On the night of September 16, 1862, Patrick’s Brigade of Doubleday’s Division bivouacked in line of battle on the east side of this road, facing west.

This tablet marks the left of the brigade line, which extended northerly about 320 yards, through a triangular strip of woods.

From the second marker on the east side of Maryland Route 65, north of Starke Avenuer:

(September 17, 1862.)

Patrick’s Brigade formed line north of Joseph Poffenberger’s at 5:30 A. M. and advanced on the east of the Hagerstwon Pike in support of Gibbon’s Brigade. It crossed the Pike and entered the West Woods at this point. The 80th New York was sent to support Battery B, 4th U. S. Artillery, 130 yards south of Miller’s barn, and the 23rd moved into the field west of this point. The 21st and 35th, in close support of Gibbon’s right, swept through the West Woods and open ground east of them in the direction of the Dunkard Church, being rejoined on the way by the 23rd. The three Regiments were checked and obliged to fall back to the cover of Miller’s barn and the rocky ledges south and west of it. After an interval of nearly an hour the three Regiments again advanced in support of Goodrich’s Brigade, Twelfth Corps, but were compelled to fall back. After the repulse of Sedgwick’s Division, the Brigade was withdrawn to a position east of the Pike in support of the Artillery of the First Corps.

From the third marker on the north side of Starke Avenue:

(September 17, 1862.)

Early in the morning of the 17th, Patrick’s Brigade advanced through the North Woods and fields east of the Hagerstown Pike and into Miller’s Cornfield in support of Gibbon’s Brigade. When Gibbon’s right deployed on the plateau and in the woods west of the Pike, Patrick crossed the Pike 230 yards north of this and entered the West Woods in support, the 80th New York was withdrawn to support Battery B, 4th U. S. Artillery, 130 yards south of Miller’s barn, and the 23rd was sent to check a movement of the enemy in the fields west of the West Woods. The 21st and 35th, in close support of Gibbon’s right, swept through the West Woods, swung to the left flank of the enemy while charging the Battery, driving them in the direction of the Dunkard Church and east of the Pike. Rejoined by the 23rd, the line advanced to the Pike but was forced back to this ledge which was held until attacked on the right flank, when it was compelled to retire to the cover of Miller’s barn and the rock ledges south and west of it.

Duty in Maryland

Battle of Fredericksburg

The regiment lost 1 man killed and 3 wounded.

Chancellorsville Campaign