Iron Brigade Facts

Key facts about the American Civil War Iron Brigade.

Rufus King portrait

On August 9, 1861, Brigadier General George B. McClellan, commander of the Army of the Potomac, issued General Orders, No. 18 (AOP) stating that “The Fifth and Sixth Wisconsin Regiments and the Nineteenth Indiana Regiment will constitute a provisional brigade, to be commanded by Brigadier General Rufus King, of the volunteer service.” King’s brigade eventually became known as the Iron Brigade. [Wikimedia Commons]

Formation Date:

  • August 9, 1861

Dissolution Date:

  • July 12, 1865

Commanders:

  • Brigadier General Rufus King (September 28, 1861–May 7, 1862), Brigadier General John Gibbon (May 7–November 4, 1862), Brigadier General Solomon Meredith (November 25, 1862–July 1, 1863), Colonel William W. Robinson (July 1, 1863–March 25, 1864), Brigadier General Lysander Cutler (March 25–May 6, 1864), Colonel William W. Robinson (May 6–June 7, 1864), Brigadier General Edward S. Bragg (June 7, 1864–February 10, 1865), Colonel John A. Kellogg (February 28–April 27, 1865), Colonel Henry A. Morrow: April 27–June 5, 1865

Significance:

  • The core of the Iron Brigade consisted of five midwestern regiments of the volunteer army, the 2nd, 6th, and 7th Wisconsin, the 19th Indiana, and the 24th Michigan, plus Battery B, 4th U.S. Artillery from the regular army.
  • The Iron Brigade was originally known as King’s Wisconsin Brigade.
  • The Iron Brigade’s formation became official on August 9, 1861, when Brigadier General George B. McClellan, commander of the Army of the Potomac, issued General Orders, No. 18 (AOP) stating that “The Fifth and Sixth Wisconsin Regiments and the Nineteenth Indiana Regiment will constitute a provisional brigade, to be commanded by Brigadier General Rufus King, of the volunteer service.”
  • The Iron Brigade’s first official designation was the 3rd Brigade of Major General Irvin McDowell’s Division of the Army of the Potomac.
  • In October 1861, the War Department reassigned the 5th Wisconsin to Hancock’s Brigade, Smith’s Division, Army of the Potomac.
  • In October 1861, the War Department assigned the 2nd Wisconsin to King’s Brigade.
  • The Iron Brigade was the only all-Western brigade assigned to the Eastern Theater.
  • The Iron Brigade was originally assigned to the defenses around Washington, D.C., following the Confederate victory at the First Battle of Bull Run (July 21, 1861).
  • In March 1862, the Iron Brigade became the 3rd Brigade, 3rd Division, 1st Army Corps, of the Army of the Potomac.
  • In April 1862, the Iron Brigade was reassigned to the newly-created Department of the Rappahannock.
  • In June 1862, the Iron Brigade was designated as the 4th Brigade, 1st Division, 3rd Army Corps, Army of Virginia.
  • The Iron Brigade saw its first combat action during the Northern Virginia Campaign (July 19– September 1, 1862).
  • On August 28, 1862, the Iron Brigade clashed with General Thomas S. Jackson’s famous Stonewall Brigade during the Battle of Brawner’s Farm.
  • The Iron Brigade suffered 800-850 casualties, including more than 200 killed during the Battle of Brawner’s Farm.
  • In September 1862, the Iron Brigade was redesignated as the 4th Brigade, 1st Division, 1st Army Corps, Army of the Potomac.
  • On September 15, 1862, the Black Hats possibly earned their illustrious nickname, “Iron Brigade” at the Battle of South Mountain.
  • On September 17, 1862, the bloodiest single day of fighting during the Civil War claimed 343 of the Iron Brigade’s remaining 800 officers and soldiers.
  • On October 8, 1862, the War Department assigned the 24th Michigan Regiment’s 838 soldiers to the Iron Brigade.
  • During the Battle of Fredericksburg (December 12–15, 1862), the Iron Brigade was charged with securing the left flank of the Union line.
  • During the Battle of Fredericksburg, the Iron Brigade suffered sixty-five casualties, including nine killed, forty wounded, and sixteen missing or captured.
  • The Iron Brigade was held in reserve at the Battle of Chancellorsville (April 30–May 6, 1863).
  • The Iron Brigade played only a small role at the Battle of Chancellorsville. Such would not be the case at the next major engagement in the Eastern Theater, the Battle of Gettysburg (July 1– 3, 1863).
  • In June 1863, the Iron Brigade was redesignated as the 1st Brigade, 1st Division, 1st Corps, Army of the Potomac.
  • The Iron Brigade was among the first units to reinforce Major John Buford’s cavalry on the first day of the Battle of Gettysburg (July 1–3, 1863).
  • During the fighting on the first day of the Battle of Gettysburg, the Iron Brigade’s resistance delayed the Confederate progress long enough for reinforcements to arrive and save the Union line.
  • At the Battle of Gettysburg, the Iron Brigade suffered the greatest proportion of the Army of the Potomac’s casualties—an astounding 61%.
  • Of the 1,883 soldiers of the Iron Brigade who fought at the Battle of Gettysburg, 1,153 were killed, wounded, or missing.
  • At the Battle of Gettysburg, the 24th Michigan (80%) and the 2nd Wisconsin (77%) suffered the second and third highest casualty rates for all battles fought during the Civil War.
  • The Iron Brigade’s all-Western composition ended on on July 16, 1863, when the 167th Pennsylvania was incorporated into it to compensate for the massive losses at Gettysburg.
  • As the Iron Brigade’s original recruits mustered out of volunteer service and returned to their homes at the end of their three-year enlistments, the War Department filled the vacancies with increasing numbers of Easterners.
  • The Iron Brigade served with the Army of the Potomac in the Bristoe (October 13–November 7, 1863), and Mine Run (November 26–December 2, 1863) Campaigns.
  • In March 1864, the Iron Brigade was attached to the 1st Brigade, 4th Division, of the 5th Army Corps.
  • The Iron Brigade served with the Army of the Potomac throughout the Overland Campaign (May 5–June 24, 1864).
  • During the Petersburg Campaign (June 1864–March 1865), the Iron Brigade’s regiments were attached to the 3rd Brigade, 3rd Division, of the 5th Army Corps in August 1864.
  • During the Petersburg Campaign (June 1864–March 1865), the Iron Brigade’s regiments were attached to the 1st Brigade, 3rd Division, 5th Army Corps in September 1864.
  • In October 1864, the 19th Indiana was folded into the 20th Indiana and went out of existence.
  • In November 1864, the 2nd Wisconsin was consolidated with the 6th Wisconsin and ceased to exist.
  • Although individual units and soldiers were dispersed, the remnants of the Iron Brigade participated in the Appomattox Campaign (March 29–April 12, 1865).
  • At the conclusion of the Civil War, the Iron Brigade’s soldiers marched with the Army of the Potomac during the Grand Review of the Union forces at Washington, D.C., on May 23–24, 1865.
  • At the conclusion of the Civil War, the original regiments of the Iron Brigade returned to their home states and mustered out of volunteer service in the following order: 24th Michigan on June 30, 1865, 6th Wisconsin (including the soldiers of the 2nd Wisconsin) and 7th Wisconsin on July 2, 1865, and the 19th Indiana (then part of the 20th Indiana) on July 12, 1865.
  • No brigade in the Volunteer Army sacrificed proportionally more in terms of human life to save the Union than the Iron Brigade.
  • Of the 7,673 soldiers who served in the Iron Brigade’s five core regiments during the Civil War, 14.7% (1,131 soldiers) were killed or mortally wounded in combat. Another 500 or so died of disease, and over 2,000 more were wounded.
  • The 2nd Wisconsin tallied the highest percentage of soldiers killed as a result of combat (19.7%) in all of the Union armies during the Civil War.
  • Of the more than 2,000 volunteer regiments that served their country, the 2nd Wisconsin, 7th Wisconsin, and 19th Indiana placed placed first, sixth and eleventh respectively on the list of the highest percentage of soldiers killed as a result of combat during the Civil War.
  • Only one regiment (the 5th New Hampshire) suffered more total deaths than the 2nd Wisconsin’s 282 during the Civil War..
  • In recognition of the sacrifice and courage of the men of the Iron Brigade, Congress awarded the Medal of Honor to seven of its members.

Citation Information

The following information is provided for citations.

  • Article Title Iron Brigade Facts
  • Author
  • Website Name American History Central
  • Access Date December 3, 2023
  • Publisher R.Squared Communications, LLC
  • Original Published Date
  • Date of Last Update August 12, 2023

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