In one of the first areas in Texas explored by the Spanish in 1690, Frio County was created in 1858 and organized in 1871. Frio City, laid out in 1871, was the first county seat, but surrendered that role to Pearsall, on the International & Great Northern Railroad, in 1883. The Old Rock Courthouse still stands in present Frio Town. The county has had four courthouses: two frame ones, one of rock, and one of brick. In 1876 a Texas Ranger camp under noted Major John B. Jones was established on Elm Creek to protect settlers from Indian attacks. The legendary frontiersman W.A.A. "Big Foot" Wallace (1817-1899) spent his last years in Frio County.