The Battle of Hoover's Gap (24 June 1863) was the principal battle in the Tullahoma Campaign of the American Civil War, in which Union General William S. Rosecrans drove General Braxton Bragg’s Confederates out of Central Tennessee. Rosecrans’ feigned move on the western end of the Confederate line had left the eastern mountain passes lightly defended, and Colonel John T. Wilder's mounted infantry achieved total surprise when they attacked Hoover's Gap. Success was attributed both to Rosecrans’ brilliant deception tactics and the high morale of Wilder’s "Lightning Brigade", equipped with the new Spencer repeating rifle. Background Following the Battle of Stones River, Maj. Gen. William Rosecrans, commanding the Union Army of the Cumberland, remained in the Murfreesboro, Tennessee, area for over five months. In an effort to block further Union progress, Confederate Gen. Braxton Bragg, commander of the Army of Tennessee, established a fortified line along the Duck River from Shelbyville to Wartrace. On the Confederate right, infantry and artillery detachments guarded Liberty, Hoover's, and Bellbuckle Gaps through the Highland Rim (near Beechgrove, Tennessee). Rosecrans's superiors, fearing that Bragg might detach large numbers of men to help break the Siege of Vicksburg, urged him to attack the Confederate positions. One of the Army of the Cumberland brigade commanders, Colonel John T. Wilder was impressed by the ability of Confederate General John Hunt Morgan to raid behind Federal lines in Kentucky. When he found that Rosecrans wanted to increase the strength of his mounted force, Wilder proposed to mount his infantry brigade by launching raids of the surrounding countryside to steal horses. Rosecrans gave him permission. By the middle of April 1863, Wilder's brigade was fully mounted. Having witnessed a demonstration of a new repeating rifle by Christopher Miner Spencer in March, Wilder determined to arm his brigade with that weapon. Wilder got his soldiers' whole-hearted support to re-arm them with the Spencer repeating rifle, and each soldier pledged a note for $35. With notes in hand, Wilder co-signed them and took out a loan from his hometown banks. Soon the brigade was armed with the new seven-shot repeaters and began performing spirited mounted service. Battle On June 23, 1863, Rosecrans deployed forces to feign an attack on Shelbyville while massing forces against Bragg's right. Union troops struck out toward the gaps. On June 24, Maj. Gen. George H. Thomas's men, spearheaded by Colonel Wilder's "Lightning Brigade", attacked Hoover's Gap. Wilder's