In the waning days of Mexican rule in the province of Alta California in 1846, history taps thirteen-year-old Guillermo Foxen on the shoulder and thrusts his family into the eye of a political storm. He's recruited by the Pathfinder himself, Lt. Col. John C. Fremont, commander of the California Battalion, to guide his invading cavalry over San Marcos Pass to retake the pueblo of Santa Barbara for the US. Will this risky action prove to be on the right side of history, or a fool's errand? In the months to come, the Foxens' role in helping the invaders is viewed as treasonous by embittered neighbors who are angry over the subsequent American takeover of their province. There are attacks on their livestock, crops are burned, and their home set on fire. Like the other vaqueros, Guillermo is forced to expand his herding duties to taking up arms to protect his family. He's proud to be descended from a long line of Spanish caballeros on his mother's side. If he were to lose his birthright, Rancho Tinaquaic, where would he find his place in this world?