Fifty-six million years ago, the proto-horse was a "twelve-pound runt" that balanced on feet with four toes. The first glimpse we have of what he looked like and how he was evolving are images found painted across the Paleolithic Lascaux Cave in southern France. Anthropologist and equestrian expert Susanna Forrest presents a singular, sweeping panorama of the animal's prominent role across time and in societies around the world. Combining fascinating anthropological detail and incisive personal anecdotes, Forrest illustrates how our evolution has coincided with that of horses. She deftly synthesizes historical material with her experience in the field, traveling the globe to give us a diverse, comprehensive look at the horse in our lives today: from Mongolia where she observes the endangered takhi, to a show-horse performance at the Palace of Versailles and then to Arlington, Virginia, where veterans with PTSD are rehabilitated through interaction with horses. Unique, passionate, and insightful, this book investigates the complexities of human and horse coexistence, brilliantly revealing the multifaceted ways our cultures were shaped by this powerful creature.