Founded in June 1852, Fort Clark guarded the California road and fought Indians and outlaws. It was named for Maj. J.B. Clark, who was killed in the Mexican War. Companies of infantry, artillery, and cavalry were stationed there, but issued clothing was too warm for summer and the buildings were too cold for winter until chimneys were built in 1856. Troops from the fort routed Indians to the mouth of the Pecos River and helped expel the bandit Cortinas from Brownsville in 1859. After Texas seceded in 1861, Union forces abandoned Fort Clark, and Texas troops occupied it for protection against Indians, seized its four 24 pounders and two 8-inch howitzers for defense of the Texas coast, and kept it occupied as part of the supply line for the Arizona and New Mexico campaign and for frontier defense, protection against bandits from Mexico, and watch against U.S. invasion along the Rio Grande. The post was reoccupied in 1866, used a Seminole Scout Company, and had an Indian reservation established nearby. Duty there in the decade after the Civil War was said to be equivalent to honorable mention. Practically all U.S. Cavalry regiments served there, the 5th Cavalry served from 1920 to 1941, the 2nd and 11th Cavalry trained there during World War II, and the post was inactivated on Feb. 9, 1946.