Tilden, the county seat of McMullen County, is at the intersection of State highways 16 and 72 in the north central part of the county. The town was probably named for Samuel J. (Whispering Sammy) Tilden, the unsuccessful Democratic presidential candidate in the election of 1876. It was one of the first two settlements in McMullen County when it was founded in 1858 at the mouth of Leoncita Creek on the Frio River. The settlement was called Rio Frio and had eight to ten crude dwellings that housed about thirty people by the fall of that year. Soon afterward the townspeople built a road connecting their settlement to the old San Antonio-Laredo road, which lay to the west. In the early 1860s the town grew slowly. In 1862 Levi J. Edwards built its first general store, and shortly after he added a saloon. About that time, too, the town built its first school. The settlement acted as a home-guard post for the Twenty-ninth Brigade of the Texas Confederate Militia during the Civil War. During the early 1860s Rio Frio became known as Dog Town. One explanation of this name holds that drunken cowboys on a shooting spree left about fifteen dead dogs on the street.
By 1870 Dog Town had a population of 190, and in 1871 the community was granted a post office. By 1876 it had four general stores, one grocery store, two saloons, a drugstore, and a hotel. In 1877, when McMullen County was officially organized, Dog Town was chosen as the county seat. The same year the site was formally surveyed, and its name was changed to Tilden. In 1879 a ferry across the Frio was established at Tilden, and about 1880 stagecoaches traveling the San Antonio-Laredo road began to make regular stops there. In 1878 the town's first church was built and was shared by Methodists and Baptists. Soon afterward, a Catholic church was also constructed, and in 1881 Tilden became the home of McMullen College. John Van Epps Covey taught there for a while. During the late 1880s and early 1890s camp meetings were also held at Tilden. In 1884 the settlement was described as a "post village" with about 250 residents, but it had the two churches, the college, a blacksmith, a cabinetmaker, two druggists, and the Tilden Ledger, a weekly newspaper. By 1890 the town had grown to 600 residents.
In 1896 Tilden's population was 450, and in 1900 it was 506. In 1897 McMullen College was formally dissolved. By 1933 the town had a population of 250 and four businesses. In 1939, possibly because of new oil production in the county, 500 people and fifteen businesses were reported. The population remained stable at 500 during most of the 1940s. In 1947 the town had ten businesses. In 1949 it had 380 people and ten businesses. In 1952 Tilden had three cafes, four service stations, two garages, four grocery stores, a drugstore, a barbershop, a lumberyard, and three churches. In 1990 the population was 500. The population dropped to 450 in 2000.