Chaves, a lineal descendent of one of the Spanish conquistadores led by Don Juan de Oñate, was born in the village of Atrisco, just west of Alburquerque, then part of the Spanish Empire.
The historian Marc Simmons speculates that Chaves's first formal military experience may have been in August, 1837, under the command of his cousin Manuel Armijo, who put down an uprising in Santa Fe and made himself governor of New Mexico, by then a province of an independent Mexico.