A Brief History of Union Cavalry in the Eastern Theatre
An Article Contributed by Eric J. Wittenburg
Civil War armies consisted of three major components: infantry, artillery, and cavalry. Cavalry played a major role. It's primary role was to support the infantry and artillery, gathering intelligence, scouting, screening the movements of the army, and serving as the "eyes and ears of the army". As the war dragged on, the Federal cavalry's role changed. Instead of scouting and screening, the primary role became that of an offensive weapon. By the end of the Civil War, the Northern cavalry had become one of the most fearsome offensive forces that the world had ever seen.
In 1861, with the coming of the war, the United States Army had several mounted units. The oldest was the First Dragoons, formed in the 1830's. In the 1840's, a second regiment of dragoons was formed, followed by the Regiment of Mounted Rifles. In the 1850's, the 1st US Cavalry was formed, which was followed by the 2nd US Cavalry in 1856. Dragoons combined most aspects of both light cavalry and mounted infantry. They carried a weapon known as a musketoon in the early days, which was a shortened musket. Later, they carried carbines. Dragoons used their horses to move them from place to place, not for fighting. Most, if not all, of their fighting was done dismounted. Light cavalry served an entirely different purpose. It was primarily intended to scout and screen an army's advance, and do whatever fighting it did do mounted, typically using either the saber or pistols.
Col. Phillip St. George Cooke of the 2nd Dragoons is generally considered to be the father of the U. S. Cavalry. In the 1850's, he wrote the tactics manual that governed the operations of the U. S. Army's mounted forces.
In 1861, with the coming of the Civil War, the US Army reorganized its mounted arm. The 1st Dragoons became the 1st US Cavalry, the 2nd Dragoons became the 2nd US Cavalry, the Regiment of Mounted Rifles became the 3rd US Cavalry, which served in the West, the 1st US Cavalry became the 4th US Cavalry (which also served in the Western Theatre), and the 2nd US Cavalry became the 5th US Cavalry, which was a fine unit. A new regiment was recruited in the summer of 1861, which became the 6th US Cavalry, which was the only Regular cavalry regiment formed during the Civil War. Its men came from the area around Pittsburgh, who typically enlisted for a term of five rather than three years.
Early Federal commanders did not make good use of the mounted arm. Maj. Gen. George B. McClellan, first commander of the Army of the Potomac, resented the volunteer cavalry, and didn't trust it. McClellan believed that it would take five years to train volunteer cavalry and get it to a point where it would be a trustworthy fighting force. As a result, he assigned individual companies of volunteer cavalry to serve with infantry brigades. Instead of doing as cavalry was supposed to do, which was to scout and screen, it served primarily as messengers and orderlies. It was, overall, and extremely poor use for the cavalry.
The only cohesive cavalry unit McClellan utilized were the Regulars, which served together as a Cavalry Reserve Brigade. They were generally used poorly, although the 5th US made a brave but ineffective mounted charge during the Battle of Gaines Mill during the Seven Days' fighting on the Peninsula during June 1862. McClellan only made one effective use of his mounted arm as part of a combined force operation commanded by G. K. Warren toward Hanover Courthouse in early June 1862. This expedition led to the destruction of bridges over the North Anna and caused Jackson to be late for the opening of the Seven Days' battles. Cooke, who proved unable to handle the responsibility of commanding a large mounted force--he had never commanded a force larger than a regiment prior to the outbreak of the Civil War. His son-in-law, the Legendary Confederate cavalry chieftain J.E.B. Stuart, rather literally rode rings around Cooke and his horsemen, and the old warrior was relieved of command, never to lead mounted forces in battle again.
Maj. Gen. John Pope received command of a new force, the Army of Virginia, in June 1862. While McClellan operated on the Virginia Peninsula, Pope was to operate in Central Virginia and the Shenandoah Valley. Pope had only volunteer cavalry forces assigned to his command. In spite of harsh orders for his troopers to live off the land, they nevertheless performed quite well under adverse circumstances. Selecting Brig. Gens. George D. Bayard and John Buford to command brigades, Pope's horsemen performed creditably. In particular, Buford's troopers did a spectacular job of gathering intelligence, and they fought well, too. The first major mounted combat of the Civil War too place under Pope's watch, and he deserves a great deal of credit for making good use of his mounted forces. However, Pope suffered a crushing defeat at Second Manassas in August 1862, and he was relieved of command. His battered army was absorbed into the Army of the Potomac during the first week of September 1862. By then, the first major Confederate invasion of the North was already underway.
His ineffective and ineffectual use of cavalry probably cost McClellan an opportunity to destroy Lee at Antietam. The cavalry spent the day "supporting the batteries" in the middle of the Federal line. One brigade was mildly involved, and a cannonball decapitated its commander. The Federal cavalry took a total of 12 casualties in the war's bloodiest single day. Instead, the cavalry should have been out scouting the flanks and guarding. If it had, it could have detected the approach of Hill's division from Harper's Ferry, and perhaps delayed its approach to Sharpsburg long enough to permit Burnside's attack to succeed. Instead, Hill made an unmolested approach, and saved the day. The ironic thing is that there were competent commanders available to McClellan. Benjamin F. "Grimes" Davis, a career horse trooper, had led the escape of a cavalry brigade from Harper's Ferry instead of surrendering, and expedition fraught with peril. He was at Antietam.
Buford was McClellan's chief of cavalry. Brig. Gen. Alfred Pleasonton commanded his troops in the field. Bayard commanded the cavalry guarding Washington. Unfortunately, McClellan had no idea how to make good use of his mounted forces. Ultimately, this poor use of the cavalry retarded the development of the Federal mounted arm for at least a year and a half, and this is the reason why the Confederate cavalry literally rode rings around the Northern army in the spring and summer of 1862.
In November, President Lincoln relieved McClellan of command and replaced him with the affable and incompetent Maj. Gen. Ambrose E. Burnside. Burnside planned and lost a terrible defeat at Fredericksburg on December 12-13, 1862, where his army crashed headlong into nearly impregnable Confederate defensive positions. The Army of the Potomac's cavalry suffered only three casualties during the battle. Unfortunately, one of them was Bayard, who was mortally wounded.
In January, 1863, Maj. Gen. Joseph Hooker replaced Burnside. Hooker immediately set about reforming the Army of the Potomac. His most innovative reform was the formation of a Cavalry Corps of approximately 12,000 men. Maj. Gen. George Stoneman commanded the corps, while Pleasonton, William W. Averell and David M. Gregg commanded the three divisions. Buford, at his own request, commanded the Reserve Brigade. On St. Patrick's Day, March 17, Averell's division, augmented by some of Buford's Regulars, met and defeated Brig. Gen. Fitzhugh Lee's cavalry brigade at Kelly's Ford. Although a relatively small action, Kelly's Ford marked the first significant victory for the Union cavalry.
Just before the Battle of Chancellorsville, Hooker sent Stoneman's Corps, less a single brigade, on an extended raid designed to cut the lines of communication between Lee's army and Richmond, the confederate capital. Although the raid was not a success, it marked the first major trial for the Federal Cavalry Corps, which performed creditable, gaining confidence. However, Hooker blamed Stoneman for the disaster that befell the Army of the Potomac at Chancellorsville, and the cavalry chief was relieved of command. Averell also took a great deal of blame for the failure, and was also relieved of command.
Pleasonton assumed corps command, and Buford took command of the First division. Col. Alfred N. Duffie assumed command of the Third Division. Not long after the great Battle of Brandy Station was fought on June 9, 1863. That day, the Federal cavalry surprised the Southern horsemen, crashing into Jeb Stuart's camps along the Rappahannock River. In a brutal day-long fight, the two forces clashed, sabres glinting in the bright spring sun. Col. Grimes Davis was killed, and the Federals took heavy casualties in the day's fighting. At the end of the day, Pleasonton withdrew, leaving the field to Stuart's battered rebels. It was the largest mounted melee of the war, with nearly 21,000 horsemen involved.
Over the next few days, the two sides fought repeatedly at Aldie, Middleburg, and Upperville, leading the way into Pennsylvania. During the Gettysburg Campaign, which began on the plains at Brandy Station, The Federal cavalry proved that to could go boot to boot with Stuart's vaunted cavaliers. By the end of the war, the Federal cavalry was the largest, best mounted, and greatest cavalry force, perhaps the greatest in history.
When the Union finally won the Civil War, it owed a great debt to its mounted arm, which provided the impetus to that victory, leading the way to Appomattox Court House, and forever ending the hopes of the Southern Confederacy.