The regiment brought 237 men in six companies (B, C, F, H, I & K) to Gettysburg.
From the monument:
Army of the Potomac
Second Division, Second Brigade
Second U.S. Infantry
Major Arthur T. Lee and Captain Samuel A. McKee Commanding
July 2 Arrived in the morning and took position with the Brigade on the right of the Twelfth Corps. Skirmished with the Confederates. Later moved to the left. At 5 p.m. formed line with left on north slope of Little Round Top and the right of Brigade line extending into some woods. Advanced across Plum Run and to the crest of the rocky wooded hill in front near the Wheatfield and facing left occupied the stone wall on the edge of the woods. The Confederates having opened fire on the right flank and advanced through the Wheatfield in the rear the Brigade was withdrawn under a heavy infantry fire on both flanks and rom the rear and of shot and shell from the Batteries and formed in line at the right of Little Round Top.
July 3 Remained in same position.
Casualties: killed 1 officer and 5 men; wounded 4 officers and 51 men; missing 6 men.
See more on the 2nd United States Infantry Regiment in the Civil War