| XX Corps | |
|---|---|
 XX Corps badge | |
| Active | 1863–1865 |
| Type | Army Corps |
| Size | Corps |
| Part of | Army of the Cumberland |
| Engagements | American Civil War |
| Commanders | |
| Notable commanders | Joseph Hooker Henry W. Slocum Alpheus S. Williams |
| Insignia | |
| 1st Division |  |
| 2nd Division |  |
| 3rd Division |  |
Two corps of the Union Army were called XX Corps during the American Civil War. Though both served in the Union Army of the Cumberland, they were distinct units and should be recognized as such.
The first XX Corps, under the command of Alexander M. McCook, was organized in the aftermath of the Battle of Stones River in January 1863 from what had been the XIV Corps, or right wing of the army, at that battle. It was so identified with its commander that it was generally referred to by other soldiers and even officers as "McCook's corps".
The corps took part in a skirmish with Bragg's rearguard at Liberty Gap, Tennessee, during the Tullahoma Campaign in June 1863. It fought its only major battle under this designation at Chickamauga, where it suffered horrendous casualties in the two days of fighting. The corps took heavy casualties, and it (along with Thomas L. Crittenden's XXI Corps), became consolidated into the new IV Corps. McCook, blamed in large part for the failure at Chickamauga, was relieved of command.
 |  |
After the Battle of Gettysburg, with the armies of the east engaged in stalemate (and a large portion of Robert E. Lee's Army of Northern Virginia, under James Longstreet, was serving with Braxton Bragg in Tennessee), Washington dispatched Joseph Hooker, discredited after his defeat at the Battle of Chancellorsville the previous May, with the XI and XII Corps of the Army of the Potomac to try to relieve Bragg's siege of Chattanooga. The command played a decisive role in the Battle of Wauhatchie, which opened up the "Cracker Line" to the besieged Union army, and seized Lookout Mountain in the famed "Battle Above The Clouds" during the early stages of the Battle of Chattanooga.
On April 4, 1864, just before the onset of the Atlanta Campaign, William T. Sherman, authorized the consolidation of XI and XII Corps as XX Corps, under Hooker's command, to serve in the Army of the Cumberland. Units from XI and XII Corps were combined in each division. The corps fought valiantly throughout the Atlanta Campaign. After James B. McPherson was killed in the Battle of Atlanta on July 22, Oliver O. Howard was made commander of the Army of the Tennessee. Hooker, partially because Howard was junior to him and partially because he blamed Howard (who had commanded XI Corps at the Battle of Chancellorsville, where it had been routed during Stonewall Jackson's famed flank march) for his part in the defeat of the Army of the Potomac, resigned. He was replaced first by Alpheus S. Williams, and then Henry W. Slocum, both former XII Corps commanders. Its troops were the first to enter Atlanta after its surrender on September 1, and later went with Sherman's Army of Georgia during his March to the Sea. Williams commanded it from then until the Carolinas Campaign (Slocum having been promoted to army command in the meantime). It played a major part in the seizure of Savannah in December and was actively engaged throughout the Carolinas Campaign, particularly at Bentonville, where it absorbed the main blow of Joseph E. Johnston's counterattack. Because fighting at Bentonville had not destroyed Johnston's army, Sherman replaced Williams with the more aggressive Joseph A. Mower. It took part in the Grand Review and was disbanded in June 1865.
Joseph Hooker was an American Civil War general for the Union, chiefly remembered for his decisive defeat by Confederate General Robert E. Lee at the Battle of Chancellorsville in 1863.
The Army of the Potomac was the primary field army of the Union army in the Eastern Theater of the American Civil War. It was created in July 1861 shortly after the First Battle of Bull Run and was disbanded in June 1865 following the surrender of the Confederate Army of Northern Virginia in April.
The Army of Tennessee was the principal Confederate army operating between the Appalachian Mountains and the Mississippi River during the American Civil War. Named for the State of Tennessee, It was formed in the same state in late 1862 and fought until the end of the war in 1865, participating in most of the significant battles in the Western Theater.
Henry Warner Slocum Sr., was a Union general during the American Civil War and later served in the United States House of Representatives from New York. During the war, he was one of the youngest major generals in the Army and fought numerous major battles in the Eastern Theater and in Georgia and the Carolinas. While commanding a regiment, a brigade, a division, and a corps in the Army of the Potomac, he saw action at First Bull Run, the Peninsula Campaign, Harpers Ferry, South Mountain, Antietam, and Chancellorsville.
The Army of Georgia was a Union army that constituted the Left Wing of Major General William T. Sherman's Army Group during the March to the Sea and the Carolinas Campaign. Although the Army of Georgia name was soon applied to this force, it was not officially recognized until March 28, 1865.
The XII Corps was a corps of the Union Army during the American Civil War.
XIV Corps was a corps of the Union Army during the American Civil War. It was one of the earliest corps formations in the Western Theater of the American Civil War.
Alpheus Starkey Williams was a lawyer, judge, journalist, U.S. Congressman, and a Union general in the American Civil War.
Baron Adolph Wilhelm August Friedrich von Steinwehr was a German-Brunswick army officer who emigrated to the United States, became a geographer, cartographer, and author, and served as a Union general in the American Civil War.
The Carolinas campaign, also known as the campaign of the Carolinas, was the final campaign conducted by the Union Army against the Confederate Army in the Western Theater of the American Civil War. On January 1, Union Maj. Gen. William T. Sherman advanced north from Savannah, Georgia, through the Carolinas, with the intention of linking up with Union forces in Virginia. The campaign culminated in the defeat of Confederate Gen. Joseph E. Johnston's army at the Battle of Bentonville, and its unconditional surrender to Union forces on April 26, 1865. Coming just two weeks after the defeat of Robert E. Lee's army at the Battle of Appomattox Court House, it signaled that the war was effectively over.
James Sidney Robinson was a U.S. Representative from Ohio and a general in the Union Army during the American Civil War. He served two terms in Congress from 1881 to 1885.
Charles Candy was a career soldier in the United States Army who served as an officer in the volunteer Union Army during the American Civil War. He commanded an Ohio regiment and, frequently, a brigade, during the war, and played a role in the defense of Culp's Hill during the July 1863 Battle of Gettysburg.
Archibald Livingston McDougall was an officer in the Union Army during the American Civil War who commanded the 123rd New York Volunteer Infantry early in the war and subsequently led a brigade at the Battle of Gettysburg.
Ezra Ayers Carman was an officer in the Union Army during the American Civil War, commanding a New Jersey infantry regiment and (occasionally) a brigade.
The 46th Pennsylvania Volunteer Infantry was a Union Army regiment in the American Civil War. It served in both the Eastern and Western Theaters, most notably at the 1862 Battle of Cedar Mountain and during the 1864 Atlanta Campaign. During the war, the regiment lost 17% of its strength through combat losses and disease.
Ariovistus Pardee Jr. was an officer in the Union Army during the American Civil War. He rose to fame during the Battle of Gettysburg, where he led the defense of a portion of Culp's Hill on July 3, 1863. A monument on the Gettysburg Battlefield commemorates the spot as "Pardee Field."
The Chattanooga campaign was a series of maneuvers and battles in October and November 1863, during the American Civil War. Following the defeat of Maj. Gen. William S. Rosecrans's Union Army of the Cumberland at the Battle of Chickamauga in September, the Confederate Army of Tennessee under Gen. Braxton Bragg besieged Rosecrans and his men by occupying key high terrain around Chattanooga, Tennessee. Maj. Gen. Ulysses S. Grant was given command of Union forces in the West which was now consolidated under the Division of the Mississippi. Significant reinforcements also began to arrive with him in Chattanooga from Mississippi and the Eastern Theater. On October 18, Grant removed Rosecrans from command of the Army of the Cumberland and replaced him with Major General George Henry Thomas.
The Battle of Bentonville was fought in Johnston County, North Carolina, near the village of Bentonville, as part of the Western Theater of the American Civil War. It was the last battle between the western field armies of William T. Sherman and Joseph E. Johnston.
The 2nd Regiment Massachusetts Volunteer Infantry was an infantry regiment in the Union Army during the American Civil War. Major George H. Gordon, a West Point graduate and veteran of the Mexican–American War, organized the unit's recruitment and formation. The 2nd Massachusetts was trained at Camp Andrew in West Roxbury, Massachusetts on the site of the former Transcendentalist utopian community, Brook Farm. Roughly half the regiment was mustered in on May 18, 1861 and the remainder on May 25, 1861 for a term of three years. The regiment saw extensive combat as part of the Army of the Potomac particularly during the Battle of Antietam and the Battle of Gettysburg.
Charles E. Winegar commanded an artillery battery in the Union service during the American Civil War.
