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XX Corps (ACW)
Encyclopedia
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.
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 (Cumberland)
. McCook, blamed in large part for the failure at Chickamauga, was relieved of command.
, 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. Hooker, partially because Howard was junior to him and partially because he blamed Howard (who had commanded XI Corps (ACW)
at 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 mean time). 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 petulant Joseph A. Mower
. It took part in the Grand Review and was disbanded in June 1865.
Corps
A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...
of the Union Army
Union Army
The Union Army was the land force that fought for the Union during the American Civil War. It was also known as the Federal Army, the U.S. Army, the Northern Army and the National Army...
were called XX Corps during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...
. Though both served in the Union Army of the Cumberland
Army of the Cumberland
The Army of the Cumberland was one of the principal Union armies in the Western Theater during the American Civil War. It was originally known as the Army of the Ohio.-History:...
, they were distinct units and should be recognized as such.
McCook's Corps
The first XX Corps, under the command of Alexander M. McCook, was organized in the aftermath of the Battle of Stones RiverBattle of Stones River
The Battle of Stones River or Second Battle of Murfreesboro , was fought from December 31, 1862, to January 2, 1863, in Middle Tennessee, as the culmination of the Stones River Campaign in the Western Theater of the American Civil War...
in January 1863 from what had been the XIV Corps
XIV Corps (ACW)
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.-Creation:...
, 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
Tullahoma Campaign
The Tullahoma Campaign or Middle Tennessee Campaign was fought between June 24 and July 3, 1863, during the American Civil War. The Union Army of the Cumberland, commanded by Maj. Gen. William S...
in June 1863. It fought its only major battle under this designation at Chickamauga
Battle of Chickamauga
The Battle of Chickamauga, fought September 19–20, 1863, marked the end of a Union offensive in southeastern Tennessee and northwestern Georgia called the Chickamauga Campaign...
, 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
XXI Corps (ACW)
XXI Corps was a corps of the Union Army during the American Civil War. It served as part of William S. Rosecrans's Army of the Cumberland and was in existence from January 9th to October 1863....
), became consolidated into the new IV Corps (Cumberland)
IV Corps (ACW)
There were two corps of the Union Army called IV Corps during the American Civil War. They were separate units, one serving with the Army of the Potomac and the Department of Virginia in the Eastern Theater, 1862–63, the other with the Army of the Cumberland in the Western Theater,...
. McCook, blamed in large part for the failure at Chickamauga, was relieved of command.
Hooker's corps
After the Battle of GettysburgBattle of Gettysburg
The Battle of Gettysburg , was fought July 1–3, 1863, in and around the town of Gettysburg, Pennsylvania. The battle with the largest number of casualties in the American Civil War, it is often described as the war's turning point. Union Maj. Gen. George Gordon Meade's Army of the Potomac...
, with the armies of the east engaged in stalemate (and a large portion of Robert E. Lee
Robert E. Lee
Robert Edward Lee was a career military officer who is best known for having commanded the Confederate Army of Northern Virginia in the American Civil War....
's Army of Northern Virginia
Army of Northern Virginia
The Army of Northern Virginia was the primary military force of the Confederate States of America in the Eastern Theater of the American Civil War, as well as the primary command structure of the Department of Northern Virginia. It was most often arrayed against the Union Army of the Potomac...
, under James Longstreet
James Longstreet
James Longstreet was one of the foremost Confederate generals of the American Civil War and the principal subordinate to General Robert E. Lee, who called him his "Old War Horse." He served under Lee as a corps commander for many of the famous battles fought by the Army of Northern Virginia in the...
, was serving with Braxton Bragg
Braxton Bragg
Braxton Bragg was a career United States Army officer, and then a general in the Confederate States Army—a principal commander in the Western Theater of the American Civil War and later the military adviser to Confederate President Jefferson Davis.Bragg, a native of North Carolina, was...
in Tennessee), Washington dispatched Joseph Hooker
Joseph Hooker
Joseph Hooker was a career United States Army officer, achieving the rank of major general in the Union Army during the American Civil War. Although he served throughout the war, usually with distinction, Hooker is best remembered for his stunning defeat by Confederate General Robert E...
, discredited after his defeat at the Battle of Chancellorsville
Battle of Chancellorsville
The Battle of Chancellorsville was a major battle of the American Civil War, and the principal engagement of the Chancellorsville Campaign. It was fought from April 30 to May 6, 1863, in Spotsylvania County, Virginia, near the village of Chancellorsville. Two related battles were fought nearby on...
the previous May, with the XI
XI Corps (ACW)
The XI Corps was a corps of the Union Army during the American Civil War, best remembered for its involvement in the battles of Chancellorsville and Gettysburg in 1863.-Formation and the Valley Campaign:...
and XII Corps
XII Corps (ACW)
The XII Corps was a corps of the Union Army during the American Civil War.The corps was formed by U.S. War Department General Order of March 13, 1862, under which the corps organization of the Army of the Potomac was first created. By that order, five different corps were constituted: one of...
of the Army of the Potomac
Army of the Potomac
The Army of the Potomac was the major Union Army in the Eastern Theater of the American Civil War.-History:The Army of the Potomac was created in 1861, but was then only the size of a corps . Its nucleus was called the Army of Northeastern Virginia, under Brig. Gen...
to try to relieve Bragg's siege of Chattanooga. The command played a decisive role in the Battle of Wauhatchie
Battle of Wauhatchie
-References:* Boatner, Mark Mayo, III. The Civil War Dictionary. New York: McKay, 1988. ISBN 0-8129-1726-X. First published 1959 by McKay.* Cozzens, Peter. The Shipwreck of Their Hopes: The Battles for Chattanooga. Urbana: University of Illinois Press, 1994. ISBN 0-252-01922-9.* Korn, Jerry, and...
, which opened up the "Cracker Line" to the besieged Union army, and seized Lookout Mountain
Lookout Mountain
thumb|right|See seven statesLookout Mountain is located at the northwest corner of the U.S. state of Georgia, the northeast corner of Alabama, and along the southern border of Tennessee at Chattanooga. Lookout Mountain, along with Sand Mountain to the northwest, makes up a large portion of the...
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
Atlanta Campaign
The Atlanta Campaign was a series of battles fought in the Western Theater of the American Civil War throughout northwest Georgia and the area around Atlanta during the summer of 1864. Union Maj. Gen. William T. Sherman invaded Georgia from the vicinity of Chattanooga, Tennessee, beginning in May...
, 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
Army of the Cumberland
The Army of the Cumberland was one of the principal Union armies in the Western Theater during the American Civil War. It was originally known as the Army of the Ohio.-History:...
. Units from XI and XII Corps were combined in each division. The corps fought valiantly throughout the Atlanta Campaign
Atlanta Campaign
The Atlanta Campaign was a series of battles fought in the Western Theater of the American Civil War throughout northwest Georgia and the area around Atlanta during the summer of 1864. Union Maj. Gen. William T. Sherman invaded Georgia from the vicinity of Chattanooga, Tennessee, beginning in May...
. After James B. McPherson
James B. McPherson
James Birdseye McPherson was a career United States Army officer who served as a General in the Union Army during the American Civil War...
was killed in the Battle of Atlanta
Battle of Atlanta
The Battle of Atlanta was a battle of the Atlanta Campaign fought during the American Civil War on July 22, 1864, just southeast of Atlanta, Georgia. Continuing their summer campaign to seize the important rail and supply center of Atlanta, Union forces commanded by William T. Sherman overwhelmed...
on July 22, Oliver O. Howard
Oliver O. Howard
Oliver Otis Howard was a career United States Army officer and a Union general in the American Civil War...
was made commander of the army. Hooker, partially because Howard was junior to him and partially because he blamed Howard (who had commanded XI Corps (ACW)
XI Corps (ACW)
The XI Corps was a corps of the Union Army during the American Civil War, best remembered for its involvement in the battles of Chancellorsville and Gettysburg in 1863.-Formation and the Valley Campaign:...
at Chancellorsville, where it had been routed during Stonewall Jackson
Stonewall Jackson
ຄຽשת״ׇׂׂׂׂ֣|birth_place= Clarksburg, Virginia |death_place=Guinea Station, Virginia|placeofburial=Stonewall Jackson Memorial CemeteryLexington, Virginia|placeofburial_label= Place of burial|image=...
's famed flank march) for his part in the defeat of the Army of the Potomac
Army of the Potomac
The Army of the Potomac was the major Union Army in the Eastern Theater of the American Civil War.-History:The Army of the Potomac was created in 1861, but was then only the size of a corps . Its nucleus was called the Army of Northeastern Virginia, under Brig. Gen...
, resigned. He was replaced first by Alpheus S. Williams
Alpheus S. Williams
Alpheus Starkey Williams was a lawyer, judge, journalist, U.S. Congressman, and a Union general in the American Civil War.-Early life:...
, and then Henry W. Slocum, both former XII Corps
XII Corps
List of military corps—List of military corps by numberA number of countries have Twelfth, or XII, Corps:*XII Corps *XII Corps *XII Corps *XII Corps *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
Army of Georgia
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.-History:...
during his March to the Sea
Sherman's March to the Sea
Sherman's March to the Sea is the name commonly given to the Savannah Campaign conducted around Georgia from November 15, 1864 to December 21, 1864 by Maj. Gen. William Tecumseh Sherman of the Union Army in the American Civil War...
. Williams commanded it from then until the Carolinas Campaign
Carolinas Campaign
The Carolinas Campaign was the final campaign in the Western Theater of the American Civil War. In January 1865, Union Maj. Gen. William Tecumseh Sherman advanced north from Savannah, Georgia, through the Carolinas, with the intention of linking up with Union forces in Virginia. The defeat of ...
(Slocum having been promoted to army command in the mean time). It played a major part in the seizure of Savannah in December and was actively engaged throughout the Carolinas Campaign, particularly at Bentonville
Battle of Bentonville
At 3 p.m., Confederate infantry from the Army of Tennessee launched an attack and drove the Union left flank back in confusion, nearly capturing Carlin in the process and overrunning the XIV Corps field hospital. Confederates under Maj. Gen. D.H. Hill filled the vacuum left by the retreating...
, where it absorbed the main blow of Joseph E. Johnston
Joseph E. Johnston
Joseph Eggleston Johnston was a career U.S. Army officer, serving with distinction in the Mexican-American War and Seminole Wars, and was also one of the most senior general officers in the Confederate States Army during the American Civil War...
's counterattack. Because fighting at Bentonville had not destroyed Johnston's army, Sherman replaced Williams with the more petulant Joseph A. Mower
Joseph A. Mower
Joseph Anthony Mower was a Union general during the American Civil War. He was a competent officer and well respected by his troops and fellow officers to whom he was known as "Fighting Joe". William T. Sherman said of Mower, "he's the boldest young officer we have".-Biography:Mower was born in...
. It took part in the Grand Review and was disbanded in June 1865.
Command History
- Joseph HookerJoseph HookerJoseph Hooker was a career United States Army officer, achieving the rank of major general in the Union Army during the American Civil War. Although he served throughout the war, usually with distinction, Hooker is best remembered for his stunning defeat by Confederate General Robert E...
, April 14, 1864 – July 28, 1864 - Alpheus S. WilliamsAlpheus S. WilliamsAlpheus Starkey Williams was a lawyer, judge, journalist, U.S. Congressman, and a Union general in the American Civil War.-Early life:...
, July 28, 1864 – August 27, 1864 - Henry W. Slocum, August 27, 1864 – November 11, 1864
- Alpheus S. Williams, November 11, 1864 – April 2, 1865
- Joseph A. MowerJoseph A. MowerJoseph Anthony Mower was a Union general during the American Civil War. He was a competent officer and well respected by his troops and fellow officers to whom he was known as "Fighting Joe". William T. Sherman said of Mower, "he's the boldest young officer we have".-Biography:Mower was born in...
, April 2, 1865 – June 4, 1865