U. S. Horse Artillery Brigade

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 regiments, 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 "drivers" riding horses pulling the guns, while the cannoneers rode on the limbers and caissons. Ordinarily, though, the cannoneers traveled on foot behind their respective gun. But,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.

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