It was supposedly named after Saint Augustine of Hippo,[3] but more plausibly, the county was named for the town of San Augustine, which had been established five years earlier and whose name was based upon an 18th-century Spanish presidio (fortress), the Presidio de San Agustín de Ahumada, named for Agustín de Ahumada, 2nd Marquess of Amarillas.

Like many areas of the South, while Republicans generally win federal and state elections, Democrats tend to perform better in down-ballot races for local offices.

Identification with the Democratic Party is strong in San Augustine County.

[12] At the federal level, San Augustine County is part of the 1st Congressional District, which is currently represented by Louie Gohmert, a Republican from Tyler.

School districts: The county is in the service area of Angelina College.

[13] American photographer John Vachon took a series of photographs of rural schoolchildren in San Augustine County, Texas, for the Farm Security Administration in 1943.