XXII Corps was a corps in the Union Army during the American Civil War. It was created on February 2, 1863, to consist of all troops garrisoned in Washington, D.C., and included three infantry divisions and one of cavalry (under Judson Kilpatrick, which left to join the Army of the Potomac during the Gettysburg campaign). Many of its units were transferred to the Army of the Potomac during Grant's Overland Campaign. At the time of the war, the Union named most of its departments, and thus its armies, after naturally occurring landmarks, specifically water courses, i.e. The Army of the Potomac, The Army of the James, The Army of the Gulf, etc. In opposition, the Confederacy named most of their Armies for geographic areas and states.
Department of the East
Comprising all of the United States east of the Mississippi River, about half of which became Confederate territory. Formed on January 1, 1861, there were many Departments formed within its borders, and finally destablished August 17, 1861. Its primary focus was to employ a chain of command to all units until the smaller departments could be formed. Headquartered in Albany, New York, it was commanded by Major General John E. Wool.
Department of Washington, D.C.
Constituted April 9, 1861, to include Washington, D.C., to its original boundaries of Arlington, Virginia, and the state of Maryland as far as Bladensburg. It was formed to center on the defense of the national capital, and to differentiate it from the Department of the East. The department was commanded by Lieutenant Colonel Charles F. Smith from April 10 through April 28, 1861, and Colonel (later Brigadier General) Joseph K. Mansfield from April 28, 1861, through the Department's dissolution on July 25, 1861.
Army of the Potomac
The Army of the Potomac, formed July 25, 1861, and destablished August 16, 1861, provide for the defense of the city of Washington, D.C. This Department was entrusted with the duty of protecting the United States' capital, with the construction of fortifications. Before the dissolution of the Department of the Potomac, most of the fortifications in the Washington, D.C., area were constructed, mainly by the regiments that were garrisoned there, most of whom had gone on to form the Army of the Potomac. Commanded by Major General George B. McClellan.
Military District of Washington
A Military District during the Civil War was a formation within a Department for the purpose of reporting directly to the department commander for administrative affairs.
The Military District of Washington was organized June 26, 1862, to include Washington, D.C.; Alexandria, Virginia; and Fort Washington, Maryland. It was a District under the Department of the Potomac. It was incorporated into the Department of the Rappahanock from April 4, 1862, through June 26, 1862, when it again became an independent command. On February 2, 1863, it merged into the Department of Washington. Commanded by Brigadier General James S. Wadsworth.
Defenses of Washington, D.C.
The Defenses of Washington D.C. was a short lived command, from September 2, 1862, through February 2, 1863. used for the consolidation of all the defenses of the area including and surrounding Washington, D.C. Its main focus was on the maintaining of the fortifications in extending in a ring around Washington, D.C. Washington, D.C., also served as a transship point for supplies and materiel destined to both the Army of the Potomac and Army of the James.
XXII Corps
thumb|The blue Pentagon Cross served as the badge of the 3rd Division, XXII Corps as well as various other XXII Corps units. During its reign, Mosby's Raiders captured Brigadier General [[Edwin H. Stoughton (then commanding the 2nd Vermont Brigade), cut telegraph wires during Early's Valley Campaign and numerous raids against rail lines and supply stations.
Battle of Fort Stevens
The corps took part in the defense of Washington during Jubal Early's Washington Raid of 1864, playing a major role in the defense of Fort Stevens on July 11, 1864. Hardin's Division held the skirmish lines and engaged in small engagements, suffering 73 killed and wounded.
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|Major General Christopher C. Augur
|October 13, 1863 – June 11, 1865
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|Major General John G. Parke
|June 7, 1865 – June 26, 1865
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Notable officers
{| class="wikitable"
!Name
!Unit
!Dates Served
|-
|Major General John G. Barnard
|Chief Engineer, Department of Washington
|July 1, 1862 — June 5, 1864
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|Major General Silas Casey
|Commanded Casey's Division (Provisional Brigade) and served as an administrative officer
|June 1862 — May 1863
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|Maj. Gen. George B. McClellan
|Commanded Department of the Potomac
|July 25, 1861 — August 16, 1861
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|Brigadier General John Joseph Abercrombie
|Commanded Abercrombie's Division
|October 1862 — June 26, 1863
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|Brigadier General Barton S. Alexander
|Chief Engineer of the Defenses of Washington, D.C.
|July 1, 1862 — April 7, 1863
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|Brigadier General Robert Cowdin
|Commanded 1st and 2nd Brigade, Abercrombie's Division
|October, 1862 — March 30, 1863
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|Brigadier General Gustavus Adolphus DeRussy
|Commander of DeRussy's Division, stationed south of Washington, D.C.
|May 25, 1863 — August 20, 1865
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|Brigadier General Martin Davis Hardin
|Commander of Haskin's Division, stationed north of Washington, D.C.
|July 8, 1864 — August 2, 1865
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|Brigadier General Joseph Abel Haskin
|Commander of Haskin's Division, stationed north of Washington, D.C., later Chief of Artillery
|February 2, 1863 — April 10, 1866
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|Brigadier General William Gamble
|Commanded Cavalry Division
|December 21, 1863 — July 17, 1865
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|Brigadier General Joseph K. Mansfield
|Commanded the original Department of Washington
|April 28, 1861 — March 15, 1862
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|Brigadier General Edwin H. Stoughton
|Commander, 2nd Vermont Brigade
|December 7, 1862 — March 9, 1863
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|Colonel John Baillie McIntosh
|Commander of Cavalry Division
|January 2, 1864 — May 2, 1864
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|Chief Aeronaut Thaddeus S. C. Lowe
|Commander of the Union Army Balloon Corps
|October 1861 — August 1863
|}
Components of XXII Corps
Many Regiments and Brigades serving in the XXII Corps were only temporarily assigned to it. Some mainly served during times when they were reconstituting due to battle casualties, while others were trained in the vicinity of Washington before going into the field. Yet others were heavy artillery regiments assigned to the fortifications surrounding the capital. Many units, including heavy artillery regiments, left when more soldiers were needed during Grant's Overland Campaign and continued through the Richmond-Petersburg Campaign until the end of the war. Some units began serving before the XXII Corps was formed.
Famed Brigades in XXII Corps
The California Brigade was formed by Oregon Senator and Colonel Edwin Baker to have a California presence in the Eastern Theater. After the death of Colonel Baker at the Battle of Ball's Bluff, the brigade was redesignated the Philadelphia Brigade. Made up of the 1st, 2nd, 3rd, and 5th California Infantry. After redesignation as the Philadelphia Brigade, it consisted of the 69th, 71st, 72nd, and 106th Pennsylvania Infantry.
The First New Jersey Brigade was a Brigade formed by the state of New Jersey while defending Washington, D.C. This was the first brigade in the Civil War to be formed with the intention of encompassing regiments from one state. It consisted of the 1st, 2nd, 3rd, 4th, and 10th New Jersey Infantry. By the end of the war, at different it would have up to eight New Jersey regiments.
The Pennsylvania Reserve Division was formed out of an overflow of volunteers over the amount requested by the Department of War. After the Secretary of War declined to accept the new units into Federal Service, they were formed, equipped and maintained by the State of Pennsylvania. During its service in Washington, D.C., it was composed of the 3rd, 4th, and 8th Pennsylvania Reserves.
Vermont gave two brigades to the defenses of Washington, D.C. The 1st Vermont Brigade, composed of the 2nd, 3rd, 4th, and 6th Vermont Infantry. It was brigaded together through the efforts of Colonel William F. "Baldy" Smith who went to his West Point classmate and friend, Major General George B. McClellan.
The 2nd Vermont Brigade, composed of 12th, 13th, 14th, 15th, and 16th Vermont Infantry, all nine-month regiments, was formed October 27, 1862.
The Iron Brigade was the only named brigade to come from varied states, the 2nd, 6th, and 7th Wisconsin Infantry, along with the 19th Indiana Infantry and was formed on October 1, 1861. Although at the time, it wasn't known by this name, simply known as 3rd Brigade, I Corps. It wouldn't earn the moniker for almost a year, during the Battle of South Mountain during the Antietam Campaign.
Connecticut
{| class="wikitable"
! Unit
! Duration
! Destination
|-
|1st Connecticut Cavalry
|April 29, 1865 — August 2, 1865
|Mustered out
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|1st Connecticut Heavy Artillery
|August 27, 1862 — May 13, 1864
|Overland Campaign
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|2nd Connecticut Heavy Artillery
|November 23, 1863 — May 13, 1864
|Overland Campaign
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|2nd Connecticut Heavy Artillery
|June 3, 1865 — August 18, 1865
|Mustered out
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|2nd Connecticut Light Artillery
|October 15, 1862 — June, 1863
|Gettysburg campaign
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|2nd Connecticut Light Artillery
|October 12, 1863 — January, 1864
|Transfer to New Orleans, Louisiana
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|5th Connecticut Infantry
|May 20, 1865 — July 19, 1865
|Mustered out
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|14th Connecticut Infantry
|May 15, 1865 — May 21, 1865
|Mustered out
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|19th Connecticut Infantry
|September 16, 1862 — November 23, 1863
|Redesignated 2nd Connecticut Heavy Artillery
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|22nd Connecticut Infantry
|October 3, 1862 — April 14, 1863
|Siege of Suffolk
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|29th Connecticut Infantry (Colored)
|April 18, 1865 — May 28, 1865
|Transfer to Brownsville, Texas
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Delaware
{| class="wikitable"
! Unit
! Duration
! Destination
|-
|Nield's Independent Battery Light Artillery
|September, 1862 — April 18, 1863
|Transfer to Norfolk, Virginia
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|1st Delaware Infantry
|May 12, 1865 - July 12, 1865
|Mustered out
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|3rd Delaware Infantry
|May 12, 1865 — June 3, 1865
|Mustered out
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|2nd District of Columbia Infantry
|September 22, 1862 — September 12, 1865
|Mustered out
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|19th Indiana Infantry
|August 5, 1861 — March, 1862
|Bull Run Campaign (Part of the Iron Brigade)
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|28th Indiana Infantry (Colored)
|April 26, 1864 — July 1, 1864
|
|-
|63rd Indiana Infantry
|May 27, 1862 — August 16, 1862
|Bull Run Campaign
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Maine
{| class="wikitable"
! Unit
! Duration
! Destination
|-
|1st Maine Heavy Artillery
|August 25, 1861 — May 15, 1864
|Overland Campaign
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|2nd Maine Light Artillery
|November 5, 1863 — April 25, 1864
|Overland Campaign
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|23rd Maine Infantry
|October 19, 1862 — June 17, 1863
|Transfer to Maine to muster out (9 month regiment)
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|31st Maine Infantry
|April 19, 1864 — May 3, 1864
|Overland Campaign
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|Baltimore Independent Battery Light Artillery
|January, 1865 — June 17, 1865
|Mustered out
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|3rd Massachusetts Cavalry
|April 20, 1865 — June 14, 1865
|Transfer to St. Louis, Missouri
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|1st Massachusetts Heavy Artillery
|May 23, 1865 — August 17, 1865
|Mustered out
|}
New Jersey
{| class="wikitable"
! Unit
! Duration
! Destination
|-
|2nd New Jersey Cavalry
|October 25, 1864 — November 9, 1863
|
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|10th New Jersey Infantry
|December 26, 1861 — April, 1863
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|}
New York
{|class="wikitable"
! Unit
! Duration
! Destination
|-
|9th New York Heavy Artillery
|September, 1862 — May 18, 1864
|
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|11th New York Infantry
|May 7, 1861 — July 15, 1861
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|}
Ohio
{|class="wikitable"
! Unit
! Duration
! Destination
|-
|131st Ohio Infantry (Detachments from)
|May 15, 1864 — August 19, 1864
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|}
Pennsylvania
{|class="wikitable"
! Unit
! Duration
! Destination
|-
|2nd Pennsylvania Heavy Artillery
|February 26, 1862 — May 28, 1864
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|5th Pennsylvania Heavy Artillery
|September 14, 1864 — June 30, 1865
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|11th Vermont Infantry
|September 22, 1862 — May 15, 1864
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|12th Vermont Infantry
|October 10, 1862 — June 25, 1863
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|13th Vermont Infantry
|October 13, 1862 — June 25, 1863
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|14th Vermont Infantry
|October 25, 1862 — June 25, 1863
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|15th Vermont Infantry
|October 26, 1862 — June 25, 1863
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|16th Vermont Infantry
|October 27, 1862 — June 25, 1863
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|}
United States Volunteers
{|class="wikitable"
! Unit
! Duration
! Destination
|-
|Veteran Reserve Corps
|
|
|-
|1st Battalion, Veteran Reserve Corps
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|2nd Battalion, Veteran Reserve Corps
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|Union Army Balloon Corps
|October, 1861 — August, 1863
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