The Battle of Devil's Backbone or Battle of Backbone Mountain was a land battle of the American Civil War on September 1, 1863 in Sebastian County, Arkansas.

After the Battle of Honey Springs, Union Major General James G. Blunt occupied Fort Smith. On September 1, he dispatched Colonel William F. Cloud with 1,500 men from the 2nd Kansas Cavalry, 6th Missouri Cavalry, two sections of Rabb’s 2nd Indiana Battery and two mountain howitzers to pursue the Confederates that had recently withdrawn from Fort Smith. Cloud chased rebel Brigadier General William L. Cabell's brigade of 1,250 men nearly 16 miles south to a village known as Old Jenny Lind. At noon, Cabell ambushed and momentarily halted his pursuers at the base of the Devil's Backbone, a prominent ridge in the Ouachita Mountains. However under the cover of artillery fire, Cloud regrouped his men and formed a line of dismounted cavalry and howitzers, which steadily drove the Southerners from their position one-fourth of a mile up the mountain side. After over three hours of fighting, the Federals finally forced the Confederates to withdraw in disorder to Waldron, where Cabell, after waiting for a full day, could only muster 900 remaining men. Cloud returned to Fort Smith, where he received "several hundred" Confederate deserters.

Battle of Devil's Backbone
Part of the American Civil War
Date September 1, 1863
Location Sebastian County, Arkansas
Result Union victory
United States United States (Union) Confederate States of America CSA (Confederacy)
Commanders and leaders
William F. Cloud William L. Cabell
2nd Kansas Cavalry
6th Missouri Cavalry
two sections of Rabb’s 2nd Indiana Battery
Cabell’s Brigade
Casualties and losses