On December 5, 1848, Capt. Seth Eastman, commander of Companies D and H, First United States Infantry, established Camp Houston as one of the first United States Army posts on the western frontier of Texas. The post was two miles southeast of Fredericksburg on Barons Creek, a tributary of the Pedernales River. This fort, part of the army's effort to protect Texan settlers and travelers from Indian depredations, served the Fredericksburg-San Antonio road and the local region. Eastman remained in Fredericksburg until February 1849, when he was ordered to move to establish a camp on the Leona River (Fort Inge). Camp Houston, or "the Camp near Fredericksburg," began with two companies, originally both infantry, then alternated between a company of infantry and one of dragoons. The German settlers in Fredericksburg had established a lasting treaty with the local Comanches in 1847; the influx of more settlers into the rich valleys of the Pedernales and its tributaries led to skirmishes but not open warfare.
The Eighth Military Department renamed the camp in December 1849 for Maj. Martin Scott (Fifth United States Infantry), who was killed at the battle of Molina del Rey in 1847. Fort Martin Scott served as a first line of defense, keeping the peace and minimizing possible friction caused by an active trade between the Comanches and German settlers. The soldiers also represented the one constant source of hard cash for businessmen in this rural community. The influx of new settlers, soldiers, and other Whites traversing the range led to the brink of open warfare in 1850, when several tribes of Indians met near the San Saba River. Indian agent John Rollins, under escort by Capt. Hamilton W. Merrill and troopers of the Second Dragoons from Fort Martin Scott, met with the Indians. This meeting culminated in the Fort Martin Scott Treaty, which improved the situation enough to prevent open hostilities.
As the settlers pushed farther west, Fort Martin Scott lost any strategic significance it might have had and became economically unjustified and militarily unnecessary because of its distance from the front line of forts. From late 1852 through 1853 the fort assumed the role of forage depot. In his report, filed in the fall of 1853, Col. W. G. Freeman recommended that the fort be closed. Consequently, the Eighth Military Department ordered that Fort Martin Scott close in December 1853.
During the Civil War the fort had no strategic position. Except as a possible site of a Confederate mustering station to serve notice against the populace of Gillespie County who had voted against secession, the Confederate Army did not occupy Fort Martin Scott. In September 1866 Gen. Philip H. Sheridan ordered elements of the Fourth United States Cavalry to Fort Martin Scott to secure the frontier once again from possible Indian depredations. By the end of 1866 the fort was finally abandoned by military units.
Though it held an important position as frontier guardian for only a short time, Fort Martin Scott served the country and state well. Many of its commanders fought in the Civil War, including William R. Montgomery, Eugene B. Beaumont, William Steele, Edward D. Blake, James Longstreet, and Theodore Fink. The Fredericksburg Heritage Association now leases the land on which Fort Martin Scott was located from the city of Fredericksburg. The association has developed the property as a park and historic site and continues with archeological projects and historic renovations.