Dalhart Grew from Two Railroads and the XIT Ranch

Dallam County was created from the Bexar District in 1876 and named for James W. Dallam, a Republic of Texas lawyer and editor. It was not officially organized until 1891, when Texline became the first county seat. The town of Dalhart didn't exist until 1901, when the Chicago, Rock Island and Pacific Railroad crossed the Fort Worth and Denver City line. The new town was briefly called 'Denrock' — a blend of Denver and Rock Island — before taking its current name from parts of Dallam and Hartley counties.

The town grew quickly as a cattle shipping point for the XIT Ranch, one of the largest ranches in Texas history. Dalhart replaced Texline as county seat after a 1903 election. The 1930s brought disaster: the Dust Bowl turned the Panhandle into a 'black duster' zone, and Dallam County lost population. Recovery came slowly through irrigation farming. Today the economy still centers on cattle and crops including wheat, corn, and sorghum.