U.S. Horse Artillery Brigade
Encyclopedia
The Horse Artillery Brigade of the Army of the Potomac
was a brigade
of various batteries
of horse artillery
during the American Civil War
.
Made up almost entirely of individual, company-strength
batteries from the Regular Army
’s five artillery
regiment
s, the Horse Artillery operated under the command umbrella of the Cavalry Corps
. The Horse Artillery differed from other light artillery (also known as "mounted" artillery) in that each member of the unit traveled on his own horse, rather than the traditional light artillery practice of some riding horses, while others rode on the limbers and caissons, with still others traveling on foot. With each man on his own horse, the unit could travel faster and more efficiently. It was the brainchild of former artillery captain and Brig. Gen.
William Farquhar Barry
, Chief of Artillery for the Army of the Potomac
, in 1861. With such a large percentage of the U.S. Horse Artillery being artillery batteries from the regular U.S. Army, it developed a superb reputation for military efficiency, accuracy of fire, and command presence in the field and in battle.
Originally under the direct command of Lt. Col.
(and future Brigadier General) William Hays
, and later under the two-brigade command of captains James Madison Robertson
and John C. Tidball
, the Horse Artillery served with distinction during most of the major engagements in the Eastern Theater
. Tidball's brigade later was commanded by Capt Dunbar R. Ransom
.
It is notable that each of these men - Barry, Hays, Robertson, and Tidball - came from the officers corps of the 2nd Regiment of Artillery. One of their chief champions, Henry Jackson Hunt
, commanded the Reserve Artillery in the Army of the Potomac, and was also an officer of the Second U.S. Artillery.
, USV (Captain, USA, 2nd U.S Artillery), of Tennessee
Battery A, 2nd U.S. Artillery
(2nd Regiment of Artillery)
Commander: Captain John C. Tidball
, USA, of Ohio
(Combined) Batteries B & L, 2nd U.S. Artillery
Commander: Captain James Madison Robertson
, USA
Battery M, 2nd U.S. Artillery
Commander: Captain Henry M. Benson, USA, of New Jersey
Battery C, 3rd U.S. Artillery
Commander: Captain Horatio Gates Gibson
, USA, of Pennsylvania
Commander: Captain James Madison Robertson
, USA
Acting Assistant Adjutant General: 1LT J.H. Bell, 6th New York Cavalry
Batteries of the First Brigade:
9th Michigan Battery, US Volunteers (6:3”)
Captain Jabez James Daniels, USV, commanding
Independent Battery, 6th New York Light Artillery, US Volunteers (6:3”)
(formerly the Artillery Company K, 9th New York State Militia, and the 83rd New York Infantry Regiment)
Commander: Captain Joseph W. Martin, USV
Batteries B & L, 2nd US Artillery (6:3”)
Commander: First Lieutenant Edward Heaton, USA
Battery M, 2nd US Artillery (6:3”)
Commander: First Lieutenant A.C.M. Pennington, Jr., USA
Battery E, 4th US Artillery (4:3”)
Commander: First Lieutenant Samuel Sherer Elder
, USA
Second Brigade, Horse Artillery
Commander: Captain John Caldwell Tidball, USA
Batteries of the Second Brigade:
Batteries E & G, 1st US Artillery (4:3”)
Commander: Captain Alanson Merwin Randol
, USA
Battery K, 1st US Artillery (6:3”)
Commander: Captain William Montrose Graham, Jr.
, USA
Battery A, 2nd US Artillery (6:3”)
Commander: Second Lieutenant John Haskell Calef
, USA
Battery C, 3rd US Artillery (6:3”)*
Commander: First Lieutenant William Duncan Fuller, USA
Light Battery H, 3rd Pennsylvania Heavy Artillery, US Volunteers (2:3”)
Commander: Captain William D. Rank, USV
Battery C, 3rd US Artillery was not present during the battle of Gettysburg
January – June, 1864
1st Brigade, U.S. Horse Artillery
Commander: Captain James Madison Robertson
, USA (Brevet Colonel)
Quartermaster: Captain William Goldie, USV (formerly Captain, 56th Illinois Infantry)
Commissary of Subsistence: Captain Henry Loud Cranford, USV (formerly First Lieutenant, 84th New York Infantry)
Organization:
9th Battery, Michigan Light Artillery
Commander: Captain Jabez Daniels, USV
6th Independent Battery, New York Light Artillery
Commander: Captain Joseph W. Martin, USV
Batteries B & L, 2nd U.S. Artillery
Commander: First Lieutenant Edward Heaton, USA
Battery D, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) Edward B. Williston, USA
Battery M, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) Alexander Cummings McWhorter Pennington, Jr.
, USA
Battery A, 4th U.S. Artillery
Commander: First Lieutenant (Brevet Captain) Rufus King, Jr.
, USA
Battery E, 4th U.S. Artillery
Commander: Captain Samuel Elder, USA
2nd Brigade, U.S. Horse Artillery
Commander: Captain John Caldwell Tidball
, USA (Brevet Lieutenant Colonel, USA; Colonel, 4th New York Artillery, USV)
Quartermaster: Captain Ira F. Payson, USV (died, July 30, 1864)
Commissary of Subsistence: First Lieutenant (Brevet Captain) William Murray Maynadier, USA
Organization:
Battery E, 1st U.S. Artillery
Commander: Captain (Brevet Major) Alanson M. Randol, USA
Battery K, 1st U.S. Artillery
Commander: Captain (Brevet Lieutenant Colonel) William Montrose Graham, USA
Battery A, 2nd U.S. Artillery
Commander: First Lieutenant Robert Clarke, USA
Section Chiefs: First Lieutenants John H. Calef, USA; N.A. Cameron, USV (TDY from 4th New York Heavy Artillery); and B.J. (Benjamin Franklin) Littlefield, USV (former US Sharpshooter, on TDY from 4th New York Heavy Artillery)
Battery G, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) John Hartwell Butler, USA
Battery C, 3rd U.S. Artillery
Commander: First Lieutenant (Brevet Major) William Duncan Fuller, USA
From June 1864
Horse Artillery Reserve, Army of the Potomac
Commander – Captain (Brevet Colonel) James M. Robertson, USA
Organization:
Batteries H&I, 1st U.S. Artillery
Commander: Captain (Brevet Major) Randol, USA
Battery K, 1st U.S. Artillery
Commander: First Lieutenant (Brevet Major) John Egan, USA
Battery A, 2nd U.S. Artillery
Commander: First Lieutenant Clarke, USA
Batteries B&L, 2nd U.S. Artillery
Commander: First Lieutenant Heaton, USA
Battery D, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Lieutenant Colonel) Edward B. Williston, USA
Battery M, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) ACM Pennington, Jr., USA (later Colonel of New Jersey Cavalry and Brevet Brigadier General, USV)
Batteries C, F,&K, 3rd U.S. Artillery
Commander: First Lieutenant (Brevet Major) James Rigney Kelly, USA (formerly enlisted Engineers Artificer and later enlisted 3rd Artillery Sergeant)
Batteries C&E, 4th U.S. Artillery
Commander: First Lieutenant Charles Lane Fitzhugh, USA, (later Colonel, 6th New York Cavalry and Brevet Brigadier General, USA and USV)
Units separated & sent to DC for further orders:
Batteries E&G, 1st U.S. Artillery
Commander: First Lieutenant David Essex Porter, USA
Battery G, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) William Neil Dennison, USA
Battery A, 4th U.S. Artillery
Commander: First Lieutenant Rufus King, Jr., USA
6th New York Independent Battery
Commander: Captain Joseph W. Martin, USV
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...
was a brigade
Brigade
A brigade is a major tactical military formation that is typically composed of two to five battalions, plus supporting elements depending on the era and nationality of a given army and could be perceived as an enlarged/reinforced regiment...
of various batteries
Artillery battery
In military organizations, an artillery battery is a unit of guns, mortars, rockets or missiles so grouped in order to facilitate better battlefield communication and command and control, as well as to provide dispersion for its constituent gunnery crews and their systems...
of horse artillery
Horse artillery
Horse artillery was a type of light, fast-moving and fast-firing artillery which provided highly mobile fire support to European and American armies from the 17th to the early 20th century...
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...
.
Made up almost entirely of individual, company-strength
Company (military unit)
A company is a military unit, typically consisting of 80–225 soldiers and usually commanded by a Captain, Major or Commandant. Most companies are formed of three to five platoons although the exact number may vary by country, unit type, and structure...
batteries from the Regular Army
Regular Army
The Regular Army of the United States was and is the successor to the Continental Army as the country's permanent, professional military establishment. Even in modern times the professional core of the United States Army continues to be called the Regular Army...
’s five artillery
Field Artillery in the American Civil War
Field artillery in the American Civil War refers to the important artillery weapons, equipment, and practices used by the Artillery branch to support the infantry and cavalry forces in the field. It does not include siege artillery, use of artillery in fixed fortifications, or coastal or naval...
regiment
Regiment
A regiment is a major tactical military unit, composed of variable numbers of batteries, squadrons or battalions, commanded by a colonel or lieutenant colonel...
s, the Horse Artillery operated under the command umbrella of the Cavalry Corps
Cavalry Corps (ACW)
Two corps of the Union Army were called Cavalry Corps during the American Civil War. One served with the Army of the Potomac; the other served in the various armies of the West.- Overview :...
. The Horse Artillery differed from other light artillery (also known as "mounted" artillery) in that each member of the unit traveled on his own horse, rather than the traditional light artillery practice of some riding horses, while others rode on the limbers and caissons, with still others traveling on foot. With each man on his own horse, the unit could travel faster and more efficiently. It was the brainchild of former artillery captain and Brig. Gen.
Brigadier general (United States)
A brigadier general in the United States Army, Air Force, and Marine Corps, is a one-star general officer, with the pay grade of O-7. Brigadier general ranks above a colonel and below major general. Brigadier general is equivalent to the rank of rear admiral in the other uniformed...
William Farquhar Barry
William Farquhar Barry
William Farquhar Barry was a career officer in the United States Army, serving as an artillery commander during the Mexican-American War and Civil War.-Birth and early years:...
, Chief of Artillery for 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...
, in 1861. With such a large percentage of the U.S. Horse Artillery being artillery batteries from the regular U.S. Army, it developed a superb reputation for military efficiency, accuracy of fire, and command presence in the field and in battle.
Originally under the direct command of Lt. Col.
Lieutenant Colonel (United States)
In the United States Army, United States Air Force, and United States Marine Corps, a lieutenant colonel is a field grade military officer rank just above the rank of major and just below the rank of colonel. It is equivalent to the naval rank of commander in the other uniformed services.The pay...
(and future Brigadier General) William Hays
William Hays (general)
William Hays was a career officer in the United States Army, serving as a Union Army general during the American Civil War.-Early life:...
, and later under the two-brigade command of captains James Madison Robertson
James Madison Robertson
James Madison Robertson was an artillery officer in the United States Army who commanded the U.S. Horse Artillery Brigade during the American Civil War.-Biography:...
and John C. Tidball
John C. Tidball
John Caldwell Tidball was a career military officer, noted for his service in the horse artillery in the cavalry in the Union Army during the American Civil War...
, the Horse Artillery served with distinction during most of the major engagements in the Eastern Theater
Eastern Theater of the American Civil War
The Eastern Theater of the American Civil War included the states of Virginia, West Virginia, Maryland, and Pennsylvania, the District of Columbia, and the coastal fortifications and seaports of North Carolina...
. Tidball's brigade later was commanded by Capt Dunbar R. Ransom
Dunbar R. Ransom
-Early life:Dunbar Ransom was born at Fayetteville, North Carolina on January 10, 1831 but moved to Vermont. He is listed as the eldest son of Col Truman B. Ransom and brother of Gen Thomas E. G. Ransom. On June 7, 1855 Ransom was appointed from civilian life as a 2nd lieutenant in the Third U....
.
It is notable that each of these men - Barry, Hays, Robertson, and Tidball - came from the officers corps of the 2nd Regiment of Artillery. One of their chief champions, Henry Jackson Hunt
Henry Jackson Hunt
Henry Jackson Hunt was Chief of Artillery in the Army of the Potomac during the American Civil War. Considered by his contemporaries the greatest artillery tactician and strategist of the war, he was a master of the science of gunnery and rewrote the manual on the organization and use of artillery...
, commanded the Reserve Artillery in the Army of the Potomac, and was also an officer of the Second U.S. Artillery.
1862 - Peninsula Campaign
Commander: Lieutenant Colonel William HaysWilliam Hays (general)
William Hays was a career officer in the United States Army, serving as a Union Army general during the American Civil War.-Early life:...
, USV (Captain, USA, 2nd U.S Artillery), of Tennessee
Battery A, 2nd U.S. Artillery
Battery A, 2nd U.S. Artillery
For this article, “Company A” and “Battery A” are interchangeable. A battery of four to six cannons, with two to three two-cannon sections was the basic unit of the artillery branch. The organization was commanded by a captain with first and second lieutenants as section chiefs and chief of...
(2nd Regiment of Artillery)
Commander: Captain John C. Tidball
John C. Tidball
John Caldwell Tidball was a career military officer, noted for his service in the horse artillery in the cavalry in the Union Army during the American Civil War...
, USA, of Ohio
- Lead (Right) Section Chief: First Lieutenant Alexander Cummings McWhorter Pennington, Jr.Alexander Cummings McWhorter Pennington, Jr.Alexander Cummings McWhorter Pennington, Jr. , was an artillery officer and brigadier general in the United States Army and a veteran of both the American Civil War and Spanish-American War.-Early life and career:...
, USA, of New Jersey - Rear (Left) Section Chief: First Lieutenant William Neil DennisonWilliam Neil DennisonWilliam Neil Dennison was a highly decorated artillery officer during the American Civil War, an attorney and business speculator during the postbellum years.-Early life:...
, USA, of Ohio - Center Section Chief: Second Lieutenant Robert Clarke, USA, of Pennsylvania
- Chief of Line of Caissons: First Sergeant Frank
(Combined) Batteries B & L, 2nd U.S. Artillery
Commander: Captain James Madison Robertson
James Madison Robertson
James Madison Robertson was an artillery officer in the United States Army who commanded the U.S. Horse Artillery Brigade during the American Civil War.-Biography:...
, USA
- Lead (Right) Section Chief: First Lieutenant John Moulder WilsonJohn Moulder Wilson-External links:* Biographical Sketch...
, USA, of Washington, DC - Rear (Left) Section Chief: Second Lieutenant Carle Augustus WoodruffCarle Augustus WoodruffCarle Augustus Woodruff , was a career soldier in the United States Army who rose to the rank of brigadier general. He received the Medal of Honor while serving as an artillery officer in the Union Army during the American Civil War.-Early life and Civil War:Woodruff was born in Buffalo, New York...
, USA, of New York - Center Section Chief: Second Lieutenant Albert Oliver Vincent, USA, of Ohio
- Chief of Line of Caissons: First Lieutenant Perry Bly, 9th New York Cavalry (on TDY)
Battery M, 2nd U.S. Artillery
Commander: Captain Henry M. Benson, USA, of New Jersey
- Lead (right) Section – First Lieutenant John W. BarlowJohn W. BarlowJohn Whitney Barlow was a career officer in the United States Army. During and after the American Civil War, he was noted for his engineering talents.-Biography:...
, USA, of New York - Rear (left) Section – First Lieutenant Peter Conover HainsPeter Conover HainsPeter Conover Hains was a major general in the United States Army, and a veteran of the American Civil War, Spanish-American War, and the First World War...
, USA, of New Jersey - Center Section – Second Lieutenant Robert Hunter Chapin, USA, of New York
Battery C, 3rd U.S. Artillery
Commander: Captain Horatio Gates Gibson
Horatio Gates Gibson
Horatio Gates Gibson was a career artillery officer in the United States Army, and brevet brigadier general in the American Civil War.-Biography:...
, USA, of Pennsylvania
- Lead (Right) Section Chief: First Lieutenant William Duncan Fuller, USA, of Maine
- Rear (Left) Section Chief: First Lieutenant Edmund Pendleton, USA, of Virginia
- Center Section Chief: First Lieutenant Henry Meinell, USA, of New York
- Chiefs of Line of Caissons: Second Lieutenant William D’Wolf, USA, of Illinois, (mortally wounded at Williamsburg, May 4, 1862; Died of wounds, June 3, 1862); Second Lieutenant Francis Lowell Dutton Russell, USA, of Massachusetts (on TDY from 4th US Artillery)
- Battery Wagon & Forge: (First?) Lieutenant J.W. Upham, 9th New York Cavalry (on TDY)
1863 - Gettysburg Campaign
First Brigade, Horse ArtilleryCommander: Captain James Madison Robertson
James Madison Robertson
James Madison Robertson was an artillery officer in the United States Army who commanded the U.S. Horse Artillery Brigade during the American Civil War.-Biography:...
, USA
Acting Assistant Adjutant General: 1LT J.H. Bell, 6th New York Cavalry
Batteries of the First Brigade:
9th Michigan Battery, US Volunteers (6:3”)
Captain Jabez James Daniels, USV, commanding
- Lead (right) Section Chief: First Lieutenant Addison Kidder, USV
- Rear (left) Section Chief: First Lieutenant Luther R. Smith, USV
- Center Section Chief: Lt. Lewis R Rage, USV
- Chief of Line of Caissons: Second Lieutenant Thomas J. Lumbocker, USV(?)
Independent Battery, 6th New York Light Artillery, US Volunteers (6:3”)
(formerly the Artillery Company K, 9th New York State Militia, and the 83rd New York Infantry Regiment)
Commander: Captain Joseph W. Martin, USV
- Lead (Right) Section Chief: First Lieutenant Moses P. Clark, USV
- Rear (Left) Section Chief: Second Lieutenant J. Wade Wilson, USV
- Center Section Chief: First Sergeant James E. Tileson, USV
Batteries B & L, 2nd US Artillery (6:3”)
Commander: First Lieutenant Edward Heaton, USA
Battery M, 2nd US Artillery (6:3”)
Commander: First Lieutenant A.C.M. Pennington, Jr., USA
Battery E, 4th US Artillery (4:3”)
Commander: First Lieutenant Samuel Sherer Elder
Samuel Sherer Elder
Samuel Sherer Elder was a career soldier in the United States Army, and a battery commander in the famed U.S. Horse Artillery Brigade.- Biography :...
, USA
Second Brigade, Horse Artillery
Commander: Captain John Caldwell Tidball, USA
Batteries of the Second Brigade:
Batteries E & G, 1st US Artillery (4:3”)
Commander: Captain Alanson Merwin Randol
Alanson Merwin Randol
Alanson Merwin Randol was an army officer in the artillery and cavalry during the American Civil War.-Biography:...
, USA
- Lead (Right) Section Chief: Second Lieutenant James Chester, USA
- Rear (Left) Section Chief: Second Lieutenant Ernest L. Kinney, USA
Battery K, 1st US Artillery (6:3”)
Commander: Captain William Montrose Graham, Jr.
William Montrose Graham, Jr.
William Montrose Graham, Jr. , was a career soldier in the United States Army, reaching the rank of major general. He was a veteran of both the American Civil War and the Spanish-American War.-Biography:...
, USA
- Lead (Right) Section Chief: First Lieutenant Teofil B. von Michalowski (or Michalows), USA
Battery A, 2nd US Artillery (6:3”)
Commander: Second Lieutenant John Haskell Calef
John Haskell Calef
John Haskell Calef was a career artillery officer in the United States Army, and a veteran of the American Civil War.-Biography:...
, USA
- Lead (Right) Section Chief: Second Lieutenant John William Roder, USA
- Rear (left) Section Chief: First Sergeant Joseph Newman, USA
- Center Section Chief: Sergeant Pergel, USA
Battery C, 3rd US Artillery (6:3”)*
Commander: First Lieutenant William Duncan Fuller, USA
- Lead (Right) Section Chief: First Lieutenant Henry Meinell, USA
- Rear (Left) Section Chief: First Lieutenant James Rigney Kelly, USA
- Center Section Chief: Second Lieutenant James Madison Lancaster, USA
- First Sergeant – First Sergeant Daniel Munger, USA
Light Battery H, 3rd Pennsylvania Heavy Artillery, US Volunteers (2:3”)
Commander: Captain William D. Rank, USV
- Lead (Right) Section Chief: William M. Runkel, USV
- Rear (Left) Section Chief: Thomas B. Nelson, USV
- Center Section Chief: Second Lieutenant John A. Light, USV
Battery C, 3rd US Artillery was not present during the battle of Gettysburg
1864 - Overland Campaign
The Horse Artillery remained organized into two brigades until June, when it was reduced to one. The units that were cut from the ranks left their best equipment with the remaining units, and reported to Washington, DC for further orders, elsewhere. The following are the final list of command and staff and order of battle of the larger organization and the list for the reduced roster.January – June, 1864
1st Brigade, U.S. Horse Artillery
Commander: Captain James Madison Robertson
James Madison Robertson
James Madison Robertson was an artillery officer in the United States Army who commanded the U.S. Horse Artillery Brigade during the American Civil War.-Biography:...
, USA (Brevet Colonel)
Quartermaster: Captain William Goldie, USV (formerly Captain, 56th Illinois Infantry)
Commissary of Subsistence: Captain Henry Loud Cranford, USV (formerly First Lieutenant, 84th New York Infantry)
Organization:
9th Battery, Michigan Light Artillery
Commander: Captain Jabez Daniels, USV
6th Independent Battery, New York Light Artillery
Commander: Captain Joseph W. Martin, USV
Batteries B & L, 2nd U.S. Artillery
Commander: First Lieutenant Edward Heaton, USA
Battery D, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) Edward B. Williston, USA
Battery M, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) Alexander Cummings McWhorter Pennington, Jr.
Alexander Cummings McWhorter Pennington, Jr.
Alexander Cummings McWhorter Pennington, Jr. , was an artillery officer and brigadier general in the United States Army and a veteran of both the American Civil War and Spanish-American War.-Early life and career:...
, USA
Battery A, 4th U.S. Artillery
Commander: First Lieutenant (Brevet Captain) Rufus King, Jr.
Rufus King, Jr.
Rufus King, Jr. was an artillery officer in the Union Army during the American Civil War, and a Medal of Honor recipient.-Family:...
, USA
Battery E, 4th U.S. Artillery
Commander: Captain Samuel Elder, USA
2nd Brigade, U.S. Horse Artillery
Commander: Captain John Caldwell Tidball
John C. Tidball
John Caldwell Tidball was a career military officer, noted for his service in the horse artillery in the cavalry in the Union Army during the American Civil War...
, USA (Brevet Lieutenant Colonel, USA; Colonel, 4th New York Artillery, USV)
Quartermaster: Captain Ira F. Payson, USV (died, July 30, 1864)
Commissary of Subsistence: First Lieutenant (Brevet Captain) William Murray Maynadier, USA
Organization:
Battery E, 1st U.S. Artillery
Commander: Captain (Brevet Major) Alanson M. Randol, USA
Battery K, 1st U.S. Artillery
Commander: Captain (Brevet Lieutenant Colonel) William Montrose Graham, USA
Battery A, 2nd U.S. Artillery
Commander: First Lieutenant Robert Clarke, USA
Section Chiefs: First Lieutenants John H. Calef, USA; N.A. Cameron, USV (TDY from 4th New York Heavy Artillery); and B.J. (Benjamin Franklin) Littlefield, USV (former US Sharpshooter, on TDY from 4th New York Heavy Artillery)
Battery G, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) John Hartwell Butler, USA
Battery C, 3rd U.S. Artillery
Commander: First Lieutenant (Brevet Major) William Duncan Fuller, USA
From June 1864
Horse Artillery Reserve, Army of the Potomac
Commander – Captain (Brevet Colonel) James M. Robertson, USA
Organization:
Batteries H&I, 1st U.S. Artillery
Commander: Captain (Brevet Major) Randol, USA
Battery K, 1st U.S. Artillery
Commander: First Lieutenant (Brevet Major) John Egan, USA
Battery A, 2nd U.S. Artillery
Commander: First Lieutenant Clarke, USA
Batteries B&L, 2nd U.S. Artillery
Commander: First Lieutenant Heaton, USA
Battery D, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Lieutenant Colonel) Edward B. Williston, USA
Battery M, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) ACM Pennington, Jr., USA (later Colonel of New Jersey Cavalry and Brevet Brigadier General, USV)
Batteries C, F,&K, 3rd U.S. Artillery
Commander: First Lieutenant (Brevet Major) James Rigney Kelly, USA (formerly enlisted Engineers Artificer and later enlisted 3rd Artillery Sergeant)
Batteries C&E, 4th U.S. Artillery
Commander: First Lieutenant Charles Lane Fitzhugh, USA, (later Colonel, 6th New York Cavalry and Brevet Brigadier General, USA and USV)
Units separated & sent to DC for further orders:
Batteries E&G, 1st U.S. Artillery
Commander: First Lieutenant David Essex Porter, USA
Battery G, 2nd U.S. Artillery
Commander: First Lieutenant (Brevet Major) William Neil Dennison, USA
Battery A, 4th U.S. Artillery
Commander: First Lieutenant Rufus King, Jr., USA
6th New York Independent Battery
Commander: Captain Joseph W. Martin, USV