Battle of Devil ' s Backbone The Battle of Devil ' s Backbone ( also known as Backbone Mountain ) was a battle of the American Civil War on September 1 , 1863 in Sebastian County , Arkansas . Devil ' s Backbone is a ridge in the Ouachita Mountains . The Union victory at Devil ’ s Backbone secured the North ’ s capture of Fort Smith ( Sebastian County ) on September 1 , 1863 . Although fighting continued in the region , Fort Smith remained a Union base until the war ’ s end . After driving other Confederate forces farther south into Indian Territory in late August 1863 , Union Major General James G . Blunt rapidly turned toward Fort Smith . Blunt ’ s troops skirmished with Confederate Brigadier General William L . Cabell ’ s brigade southwest of Fort Smith on August 31 . Cabell decided to retreat southeast and sent his baggage and ordnance wagons off that evening . Discovering this Confederate retreat the next morning , Blunt took an infantry regiment and captured Fort Smith without incident , while Colonel William F . Cloud led about 700 Union cavalry and artillery men in pursuit of Cabell . After retreating down the road toward Waldron , Arkansas in Scott County , Cabell turned around to buy time for his slow - moving wagons to escape . His total force numbered 1 , 250 , but probably not all participated in the ensuing action . Morale was a problem ; some of Cabell ’ s troops were described as deserters , conscripts , and jayhawkers , with little interest in the Confederate cause . Cabell concealed a reliable cavalry regiment at the base of Devil ’ s Backbone , a ridge crossed by the road . Three unreliable cavalry units were stationed on the hillside beside the road , with an artillery battery and an infantry regiment posted a few hundred yards up the slope behind the cavalry . At noon , Cabell drew first blood when Cloud ’ s advance guard blundered into the concealed cavalry regiment ’ s ambush . The advance guard ’ s survivors fell back in confusion as the Confederate battery began firing on the rest of Cloud ’ s arriving command . The Union troops deployed their artillery across the road ; it went into action as Cloud ’ s cavalrymen dismounted , formed to either side of the road , advanced to the base of the ridge , and began to ascend the slope . The concealed Confederate cavalry regiment retired before this advance even though Cloud ’ s troops had not yet opened fire . At this point , Cabell ’ s other units demonstrated their unreliability . An officer with Cabell ’ s infantry regiment recalled , “ As the Yankees came in musket range of Cabell ’ s leading regiment , it stampeded without firing a shot and running into and through the two regiments in its rear , stampeded them and the whole combined mass ran through the left wing of Cabell ’ s infantry regiment and swept them off the field . ” In an instant , Cabell ’ s force was reduced to one cavalry regiment , the battery , and part of the infantry regiment . Cloud pushed his dismounted cavalrymen to within a quarter of a mile of the Confederate line on the ridge ’ s summit . The action degenerated into a small - arms and artillery skirmish of three hours . Cabell directed the fire of the Confederate battery as Cloud ’ s men made occasional demonstrations of attacking , but no attack materialized ; the parties were content to trade fire without close combat . The action claimed the lives of two Union troops ; twelve were wounded , and two went missing . Confederate casualties included five killed , twelve wounded , and thirty captured . When the action ended , both sides claimed victory . Cloud reported that the Confederates suddenly retreated during a suspension of Union gunfire . Cabell may have misinterpreted this suspension , because he reported that Cloud was repulsed and that the Confederates then withdrew . In any event , the Union held the field at the action ’ s conclusion . All contact ceased with Cabell ’ s withdrawal . He reached Waldron the next day , and Cloud returned to Fort Smith . By capturing Fort Smith and defeating Cabell at Devil ’ s Backbone , the Federal forces gained a foothold in the Arkansas River Valley . From this base , Federal units would battle Confederate partisans , march to participate in the April 1864 Camden Expedition , and support Federal efforts in Indian Territory . While the later Battle at Massard Prairie in July 1864 demonstrated Fort Smith ’ s vulnerability , it nonetheless remained a Federal outpost for the rest of the war .