Deaf Smith County was cattle country first; the railroad built Hereford

Deaf Smith County was created from the old Bexar District in 1876. It is named for Erastus 'Deaf' Smith, a scout who served during the Texas Revolution. Early settlement was dominated by large ranches including the XIT, T Anchor, and LS spreads. The first county seat, La Plata, was chosen in 1890. When the Pecos and Northern Texas Railway (a Santa Fe line) laid tracks across the county in the late 1890s, a new town grew up along the line. That town — originally called Blue Water, then renamed after the Hereford cattle breed — quickly became the main commercial hub.

An 1898 election moved the county seat to Hereford, where it has stayed. Farming expanded through the early 1900s; wheat was a major crop by 1930. Large cattle feedlots arrived in the 1960s and by the 1970s fed about 80 percent of the county's income. Today Deaf Smith County sits at about 3,200–4,200 feet elevation and receives roughly 17 inches of rain per year — conditions that shaped its dry-land and irrigated farm economy.