Site 16 miles southwest on Rio Grande on old military and stage road from San Antonio to El Paso. When U.S. posts were surrendered at outbreak of civil war, designated part confederate far western frontier defense line. Occupied by unit of Texas mounted rifles. On supply and communication line for troops to and from 1861-1862 Arizona-New Mexico campaign designed to make the Confederacy an ocean to ocean nation. Occupied briefly by Union troops from California, August 1862. 90,000 Texas troops served the South. Source of supply and gateway to vital trade thru Mexico, Texas was storehouse of the western Confederacy. Texas also had to guard a 2000 mile frontier and coastline from Union troops and the constant threat of savage Indians. 400 miles east, frontier defenders set up a line of camps, separated by a day's ride, from the Red River to the Rio Grande. A few Confederate troops joined by rangers, the organized militia, and citizens' posses held on until war's end though short on mounts and arms.