Robert R. Russell's widow and son Andrew J. were still in Claiborne County 1880-1900 so Robert did die there 1870s. And although he didn't die in the war, he would have been familiar with the area, as indicated by the National Park Service's list of 3rd Cav service:

CONFEDERATE MISSOURI TROOPS
3rd Battalion, Missouri Cavalry

3rd Cavalry Battalion was formed early in 1862 with about 400 officers and men. Ordered east of the Mississippi River, the unit was dismounted. It took an active part in the conflicts at Iuka and Corinth, then was assigned to General Buford's Brigade in the Department of Mississippi and East Louisiana. The battalion was involved in the Vicksburg operations and in November, 1863 consolidated with the 1st Missouri Cavalry Regiment. Assigned to General Cockrell's Brigade, it fought in the Atlanta Campaign and in Tennessee with Hood. Later it shared in the defense of Mobile. The unit lost more than twenty-five percent of the 388 engaged at Iuka and sustained 100 casualties at Corinth. During the Atlanta Campaign, May 18 to September 5, the 1st/3rd Battalion reported 25 killed, 80 wounded, and 3 missing, and there were 56 disabled at Allatoona. Few surrendered in May, 1865. Its commanders were Lieutenant Colonels L.C. Campbell and D.Todd Samuel, and Major Thomas J. McQuiddy.