The Texas legislature created four and a half dozen counties in the Panhandle and South Plains on Aug. 21, 1876, but it took more than drawing lines on a map to populate the last frontier in the Lone Star State.

The region was still cattle country well into the 1890s with only a scattering of villages like Clarendon and Tascosa. But the coming of the railroad, improvements in agriculture and a steep drop in beef prices, that made the ranchers’ range more valuable as farmland, set the stage ...