Manchaca is ten miles southwest of Austin in southwestern Travis County. It was named for nearby Manchaca Springs, where José Antonio Menchaca once camped. In 1851 a post office known as Manchac House opened two miles south of the present townsite, with William Pelham as postmaster; the office was discontinued the next year. A second office, called Manchac, was in operation at the present townsite between June 1874 and May 1875; after it closed, mail for area residents was sent to nearby Onion Creek. In 1881 the International-Great Northern Railroad completed its track between Austin and Laredo, giving the small community new life. With the railroad in 1881 came a third post office, now spelled Manchaca (pronounced "Manshack"). By 1884 Manchaca had seventy-five residents and served as a shipping point for grain, cotton, posts, and lumber. A school, a hotel, and a Methodist church were added in the 1890s. The community became the focus of a common school district, which in the 1930s had two grade schools for White students and one grade school for Black students. The district joined with Oak Hill in 1961 to form a rural high school district and was annexed to the Austin Independent School District in 1967. Manchaca reported a population of 200 in the late 1960s, but the number of residents reported there fell to thirty-six in the 1970s. Local development in the mid-1980s brought a growth spurt to Manchaca, and its population had increased to 4,700 by 1990. The population dropped to 2,259 by 2000.