The Second Battle of Bull Run, also known as Second Manassas, began on Thursday, August 28, 1862, when Confederate forces under “Stonewall” Jackson attacked Union forces moving along Warrenton Turnpike just outside Gainesville, Virginia, near the farm of John Brawner. Jackson’s intent was to hold General Pope and the Army of Virginia until Major General Longstreet arrived with the remainder of the Army of Northern Virginia. The first day of the battle ended in a stalemate.
Robert Patterson’s 61st OVI was part of the the I Corps under Major General Franz Sigel. Sigel’s I Corps was positioned along the Manassas-Sudley Road. On August 29, the I Corps was ordered to attack Jackson’s left at daybreak. Sigel, unsure of Jackson’s dispositions, chose to advance along a broad front. The 61st OVI, positioned on the right as part of Brig. General Carl Schurz’ division, made first contact with Jackson’s forces about 7 a.m. as they moved north on the Manassas-Sudley Road. This action was part of a series of small, disjointed attacks made by Pope against Jackson’s forces on August 29. While Pope focused on Jackson, he was unaware that General Robert E. Lee and Major General James Longstreet arrived with the rest of the Army of Northern Virginia.
Pope’s mild successes on August 29 encouraged him to resume the attack on August 30. Late in the afternoon Lee, seeing an opportunity to attack, ordered Longstreet to counterattack an exposed Union left flank. Pope facing disaster, patched together a series of makeshift defenses in an effort to save his army. Darkness finally ended the battle and during the night Pope withdrew his forces toward Washington, D.C. On their retreat to Washington they met troops from McClellan’s Army of the Potomac who were marching to assist them.
The 61st OVI was heavily engaged in the battle on August 29 and 30. One report, from a Captain Becket of F Company, stated that on August 29 they “were under constant fire for nine hours.” On Saturday, August 30, the regiment supported “Dilger’s battery, which it did until ordered off the field about 9 o’clock. It was the last regiment to leave the field.” (Robert G. Carroon’s history of the 61st OVI).
Following the battle, the 61st OVI covered the retreat of the Union Army on Centerville Turnpike toward Washington, D.C. On September 2 the regiment briefly skirmished with Confederate forces at Fairfax Court House and then fell back to Chain Bridge. It remained camped between Washington, D.C. and Centerville until October 2, 1862. The regiment was then assigned to the XI Corps under Major General Franz Sigel. The XI Corps was part of a reserve force of 47,000 soldiers under Major General Nathaniel P. Banks that was ordered to protect the capital. Because of this assignment, the 61st did not participate in the Battle of Antietam.
During the Second Battle of Bull Run, the 61st lost 25 men killed or wounded and 7 missing or captured.