The predominately Irish 6th Louisiana Infantry Regiment fights at the Battle of Chantilly (or Ox Hill, the Confederate name), which takes place on September 1, 1862, in Fairfax County, Virginia, as the concluding battle of the northern Virginia campaign of the American Civil War. Thomas J. “Stonewall” Jackson‘s corps of the Army of Northern Virginia attempts to cut off the line of retreat of the Union Army of Virginia following the Second Battle of Bull Run but is attacked by two Union divisions. During the ensuing battle, Union division commanders Isaac Stevens and Philip Kearny are both killed, but the Union attack halts Jackson’s advance.

On the morning of September 1, 1862, Union Maj. Gen. John Pope orders Maj. Gen. Edwin Vose Sumner of the II Corps, Army of the Potomac, to send a brigade north to reconnoiter. The army’s cavalry is too exhausted for the mission. But at the same time, he continues his movement in the direction of Washington, D.C., sending Maj. Gen. Irvin McDowell‘s III Corps to Germantown (on the western border of modern-day Fairfax, Virginia), where it can protect the important intersection of Warrenton Pike and Little River Turnpike that the army needs for the retreat. He also sends two brigades from Maj. Gen. Jesse L. Reno‘s IX Corps, under the command of Brig. Gen. Isaac Stevens, to block Jackson. Maj. Gen. Philip Kearny’s division from the III Corps follows later that afternoon.

Jackson resumes his march to the south, but his troops are tired and hungry and make poor progress as the rain continues. They march only three miles and occupy Ox Hill, southeast of Chantilly Plantation, and halt, while Jackson himself takes a nap. All during the morning, Confederate cavalry skirmish with Union infantry and cavalry. At about 3:00 PM, Stevens’s division arrives at Ox Hill. Despite being outnumbered, Stevens chooses to attack across a grassy field against Brig. Gen. Alexander Lawton‘s division in the Confederate center. The Union attack is initially successful, routing the brigade of Colonel Henry Strong and driving in the flank of Captain William Brown, with Brown killed during the fighting. The Union division is driven back following a counterattack by Brig. Gen. Jubal Early‘s brigade. Stevens is killed during this attack at about 5:00 PM by a shot through his temple.

A severe thunderstorm erupts about this time, resulting in limited visibility and an increased dependence on the bayonet, as the rain soaks the ammunition of the infantry and makes it useless. Kearny arrives about this time with his division to find Stevens’s units disorganized. Perceiving a gap in the line he deploys Brig. Gen. David B. Birney‘s brigade on Stevens’s left, ordering it to attack across the field. Birney manages to maneuver close to the Confederate line but his attack stalls in hand-to-hand combat with Maj. Gen. A.P. Hill‘s division. Kearny mistakenly rides into the Confederate lines during the battle and is killed. As Kearny’s other two brigades arrive on the field, Birney uses the reinforcements as a rear guard as he withdraws the remainder of the Union force to the southern side of the farm fields, ending the battle.

That night, Maj. Gen. James Longstreet arrives to relieve Jackson’s troops and to renew the battle the following morning. The lines are so close that some soldiers accidentally stumble into the camps of the opposing army. The Union army withdraws to Germantown and Fairfax Court House that night, followed over the next few days by retreating to the defenses of Washington D.C. The Confederate cavalry attempts a pursuit but fails to cause significant damage to the Union army.

The fighting is tactically inconclusive. Although Jackson’s turning movement is foiled and he is unable to block the Union retreat or destroy Pope’s army, National Park Service historians count Chantilly as a strategic Confederate victory because it neutralizes any threat from Pope’s army and clears the way for Lee to begin his Maryland campaign. The Confederates claim a tactical victory as well because they hold the field after the battle. Two Union generals are killed, while one Confederate brigade commander is killed. Pope, recognizing the attack as an indication of continued danger to his army, continues his retreat to the fortifications around Washington, D.C. Lee begins the Maryland Campaign, which culminates in the Battle of Antietam, after Pope retreats from Virginia. The Army of the Potomac, under Maj. Gen. George B. McClellan, absorbs the forces of Pope’s Army of Virginia, which is disbanded as a separate army.

The site of the battle, once rural farmland, is now surrounded by suburban development in Fairfax County. A 4.8-acre (19,000 m²) memorial park, the Ox Hill Battlefield Park, is located off of State Route 608 (West Ox Road) and lies adjacent to the Fairfax Towne Center shopping area and includes most of the Gen. Isaac Stevens portion of the battle, about 1.5% of the total ground. The park is under the jurisdiction of the Fairfax County Park Authority. In January 2005, the Authority approves a General Management Plan and Conceptual Development Plan that sets forth a detailed history and future management framework for the site.

A small yard located within the nearby Fairfax Towne Center has been preserved to mark the area crossed by Confederate troops to get to the Ox Hill battlefield.

(Pictured: Color lithograph “General Kearney’s gallant charge,” published by John Smith, 804 Market St., Philadelphia. From the Library of Congress.)