Cavalry Corps (Union Army)

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.

In contrast to the Confederacy, which early on spawned such brilliant cavalry leaders as J.E.B. Stuart, Nathan B. Forrest, and John S. Mosby, the Union high command initially failed to understand the proper way to use cavalry during the early stages of the war. At the time, cavalry units in the Union armies were generally directly attached to infantry corps, divisions, and "wings" to be used as "shock troops," and essentially played minimal roles in early Civil War campaigns. The Union cavalry was disgraced by Stuart's raids during the Peninsular, Northern Virginia, and Maryland Campaigns, where Stuart was able to ride around the Union Army of the Potomac with feeble resistance from the scant Federal cavalry. The Federals rarely even used cavalry as scouts or raiders in the early days of the war. Only a handful of Union cavalry officers, George Bayard, Benjamin Grierson, and John Buford among them, distinguished themselves in a positive way in the first two years of the war.

After the disastrous Fredericksburg Campaign, Maj. Gen. Joseph Hooker took command of the Army of the Potomac. One of Hooker's positive contributions was in creating a unified cavalry command in April 1863. Other than at Antietam, where the cavalry had been combined into a single division for a planned (but unengaged) attack on Lee's center, the Union cavalry had not been unified to date. Hooker organized three previously unrelated divisions into a single corps of cavalry, placing it under the unified command of George Stoneman. Hooker also began outfitting them with Sharps and Smith breechloading rifles, and, in a couple cases, with Spencer repeating rifles, giving them an advantage in firepower over the Confederates.

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