Fort Mason ( Texas ) Fort Mason was established July 6 , 1851 in what later became Mason County . It was named in honor of Lieut . George Thomson Mason , United States Army Second Lieutenant killed in the Thornton Affair during the Mexican – American War near Brownsville , April 25 , 1846 . At various times from 1856 to 1861 this was the home fort for Albert Sidney Johnston , George H . Thomas , Earl Van Dorn and Robert E . Lee . The fort was abandoned by the military in the 1870s , and restored by a group of local citizens in 1975 . Designated a Recorded Texas Historic Landmark in 1936 Marker number 11275 . History . Fort Mason , Texas was established by the United States War Department as a front - line defense against Kiowa , Lipan Apache and Comanche , on July 6 , 1851 . The site on Post Oak Hill near Comanche and Centennial creeks was chosen by Lieutenant Colonel William J . Hardee and surveyor Richard Austin Howard . Bevet Major Hamilton W . Merrill , along with companies A and B of the Second Dragoons , established the fort itself . Originally part of Gillespie County , Mason County was named for the fort when it was established in 1858 . Comanche chief Katemcy at one point turned over two white captives aged 11 and 12 , and again bringing them back when the captives ran away from the fort to reunite with the Comanches . The fort was closed in January 1854 , after which horse theft by native Americans was reported and pursued by the military . It was reoccupied in 1856 by Company A , First Dragoons , from March to May and was occupied by companies B , C , D , G , H , and I of the Second United States Cavalry from January 14 , 1856 , with Col . Albert Sidney Johnston in command . Among those stationed at Fort Mason before the Civil War , George H . Thomas and Philip St . George Cooke became generals for the Union Army , while those who became generals for the Confederate States Army included Earl Van Dorn , Fitzhugh Lee , E . Kirby Smith , Robert E . Lee , John Bell Hood , William J . Hardee . Fort Mason was Robert E . Lee ' s last command with the United States Army . In a letter home on January 23 , 1861 , Lee wrote : Fort Mason was evacuated by Federal troops , March 29 , 1861 and reoccupied after the Civil War until 1869 . Confederacy . The Confederate States Army took control of Fort Mason on March 29 , 1861 . In 1862 , the CSA held 215 men prisoner , who were transferred to Austin in 1862 . United States Army reoccupation . The United States Army reoccupied the fort on December 24 , 1866 . under the command of General John Porter Hatch . During this period , the fort was renovated with both civilian and military labor . Indian depredations had increased during the Civil War and were worse when the Army returned . The lawlessness of the Reconstruction era of the United States through the military personnel , many of who deserted or were subjected to military discipline . By January 13 , 1869 , there were twenty - five buildings , either unoccupied or in poor shape , and less than seventy soldiers . The order to close the fort was carried out on March 23 , 1869 . During 1870 the state of Texas organized several companies of frontier forces . Fort Mason was reopened in September of that year as headquarters for Companies A and B , Frontier Forces , under Capt . James M . Hunter , later county judge of Mason County . The fort was closed for good in 1871 . Restoration . Mason citizens recycled material from the fort when building their own homes . A restoration of the fort began in 1975 . Today , the fort belongs to the Mason County Historical Society .