Mathis is a city in San Patricio County, Texas, United States. The population was 5,034 at the 2000 census. In 1887 when the San Antonio and Aransas Pass Railroad was laying tracks across San Patricio County, Thomas H. Mathis got naming rights when he donated 300 acres (1.2Square kilometers) for a townsite and school. Mathis could well afford 300 acres (1.2Square kilometers) since he and his brother J. M. Mathis, held 37,000 acres (150Square kilometers) in the vicinity. The brothers had dropped out of the Coleman, Mathis, Fulton Cattle Company in 1879. Thomas Mathis owned an additional 60,000 acres (24Square kilometers) around Mathis and built a fence enclosing the town. Mathis' success was partially fueled by residents of Lagarto moving to be near the railroad. The Mathis Post office opened in 1890 and the towns first school was held in a private residence in 1893. Two years later a one-room school built and in 1913 a second railroad (The San Antonio, Uvalde and Gulf Pacific) arrived.