Established July 6, 1851 by the U. S. Army as a protection to the frontier. Named in honor of Lieut. George T. Mason, killed in action near Brownsville, April 25, 1846. Albert Sidney Johnston, George H. Thomas, Earl Van Dorn and Robert E. Lee, of the 2nd U. S. Cavalry, were stationed here at intervals from 1856 to 1861. Evacuated by Federal troops, March 29, 1861 and reoccupied after the Civil War until 1869. (1936)