The county is named for local rancher Antonio Zapata. In 1821 the future Zapata County, along with other settlements between the Nueces and the Rio Grande, became part of the Mexican state of Tamaulipas. From the Texas Revolution until the Mexican War the region was disputed territory, claimed by both Texas and Mexico. In 1848 the Treaty of Guadalupe Hidalgoqv established the Texas claim to the region, and the area of future Zapata County was included in Starr and Webb counties. On January 22, 1858, the legislature passed a measure establishing Zapata County, which was organized on April 26, 1858, with Bellville (later known as Carrizo and subsequently as Zapata) as the county seat. After a district judge, a clerk, and various other county officials were killed in a raid by outlaws in 1875, Governor Richard Coke declared that until order was restored all county judicial proceedings should take place in neighboring Webb County. -Handbook of Texas Online: Zapata County