Before the Mexican-American War concluded in 1848, American traders who traveled to the Western frontier encountered Spanish vaqueros of northern Mexico. The arrival of railroads and an increased demand for beef during the Civil War drove the need for the cowboy. The earliest known photographs of these iconic Americans are tintypes, taken as early as the 1870s, most likely captured during a trail drive or at an end-of-trail town. The Texas Live Stock Journal wrote glowingly of the cowboy on October 21, 1882: “A man wanting in courage would be as much out of place in a cow-camp, as a...