On a hot July dawn in 1853, a gunfight took place on the western edge of the San Joaquin Valley, midway between San Francisco and Los Angeles. When the smoke cleared, Joaquin Murrieta, one of the most notorious bandits of the Gold Rush lay dead. Soon his severed head was traveling around the new state of California in a pickling jar. Murrieta would have an unparalleled afterlife in dime novels and movies, Mexican folksongs and Gold-Rush legends. Anglos...