In 1721, Spain established a fort and mission on the Texas-Louisiana border, or frontera, to stem the tide of people and goods flowing back and forth between northern New Spain and French Louisiana. Named in part for the indigenous Adai people, the complex of the presidio (Nuestra Senora del Pilar de los Adaes) and the mission (San Miguel de Cuellar de Los Adaes) became collectively know as Los Adaes. It was the capital of Tejas for New Spain. This is the first book devoted to Los Adaes, and Dr. Galan shows that Spain could neither block settlers and smuggled goods nor convert the the native Americans to Christianity and the Spanish economic system. In 1762 Spain closed the fort and mission. Some returned to Nacogdoches and some to San Antonio.