Third Corps

On July 1, the Army of the Potomac's Third Corps, under Major General Daniel E. Sickles and Major General David B. Birney, was at Emmitsburg complying with General Howard's urgent request received at 3.10 p.m., and Sickles marched the corps, except two brigades and two batteries, to Gettysburg. At daybreak on July 2, these troops rejoined the corps massed on the left of Cemetery Ridge. During the forenoon the Confederates advanced toward the Union left, and a reconnaissance disclosed their formation in three columns. With Buford's Cavalry Division on the left flank withdrawn, at about 2 p.m. this corps, then the extreme left of the Union line, changed front to check the enemy until the 5th Corps could march from the Union right and occupy the Round Tops. The 3rd Corps, about 9800 men, formed line of battle from Plum Run to the Peach Orchard, then along the Emmitsburg Road 300 yards past the Roger House, with Birney's Division on the left and Humphreys' Division along Emmitsburg Road against three divisions, about 17000 strong, under Longstreet. Confederate batteries opened about 3 o'clock, and infantry advanced soon after against the 3rd Corps left. Following an oblique order of battle, at 5.45 p.m. the enemy attacked the 3rd Corps left centre. Reinforcements repulsed this attack and occupied the Round Tops, relieving Birney's Division except at the Peach Orchard. About 6.30 p.m. the 3rd Corps centre at the Peach Orchard was broken after a stubborn resistance, uncovering the left of Humphreys' Division, which changed front and slowly retired, following Birney to Cemetery Ridge and again advancing to the Emmitsburg Road, held that line until morning, the battle continuing until 7.30 p.m. General Sickles was severely wounded about 6 o'clock, and General Birney took command. On July 3, the corps was in support of the left centre on Cemetery Ridge. Its casualties were 593 killed, 3029 wounded, and 589 missing, for a total of 4211.

Pennsylvania · United States