"Draw a map for me so I can understand it," a prominent physicist once said when presented with a bold new theory. The history of Texas is here made understandable through its changing maps--an atlas of Texas' geographical and political evolution. From the early boundaries of New Spain, through the 23 poorly defined territories (called municipalities) that existed in 1836, to the 254 governmental bodies we know as counties, the drawing of these geo-political units reflect both the history of the state and the passions and philosophy that underlie it. The steady progression of Texas county...