Post, the county seat of Garza County, is on the Santa Fe Railroad at the junction of U.S. highways 84 and 380, east of the Caprock escarpment near the west central part of the county. The town began under the name Post City in 1907 as a colonizing venture of cereal manufacturer Charles William Post, who sought to develop a model town. He purchased 200,000 acres of ranchland and established the Double U. Company to manage the town's construction.
The company built trim houses and numerous structures, which included the Algerita Hotel, a gin, and a textile plant. They planted trees along every street and prohibited alcoholic beverages and brothels. The Double U. Company rented and sold farms and houses to settlers. A post office began in a tent during the year of Post City's founding. Two years later the town had a school, a bank, and a newspaper, the Post City Post. The railroad reached the town in 1910. The town changed its name to Post when it incorporated in 1914, the year of C. W. Post's death. By then Post had a population of 1,000, ten retail businesses, a dentist, a doctor, a sanitarium, and Baptist, Methodist, and Presbyterian churches. The Post estate pledged $75,000 and the town raised $35,000 in 1916 to bid unsuccessfully to become the site of the proposed West Texas Agricultural and Mechanical College, later known as Texas Tech University. Postex Cotton Mills, which began production in 1913 with 250 employees, has remained the town's leading industry. When the Post interests sold the business to Ely and Walker Dry Goods Company of St. Louis in 1945, the plant was producing six million yards of cloth a year and employed 375 workers who manufactured Postex cotton sheets and Garza pillow cases. Ely and Walker sold Postex in 1955 to Burlington Industries, the world's largest textile manufacturer at that time. By 1973 the company employed 450 persons. Oilfield service companies have been important to the economy, as have farming and ranching.
In 1989 Post had two libraries, a hospital, a nursing home, an airport, the Post Dispatch (founded in 1926), and ninety businesses. The population reached 3,400 in 1928, declined to 2,000 in 1940, and increased to 3,100 during the 1950s. With the development of the local oil industry, the town's population attained its highest level of 4,800 in 1964. The 1980 census showed a population of 3,864, but by 1988 the Texas Almanac reported 4,162. In 1990 the population was 3,768. The population was 3,708 in 2000.