 In 1823 the governor of New Mexico, José Antonio Vizcarra, discovered ancient ruins in the canyon during a military campaign against the Navajo.Vizcarra's account is the first historical record of the Chacoan great houses that were "of such antiquity that their inhabitants were not known to Europeans".In 1844, Josiah Gregg made the first published reference to Chaco Canyon in his popular book, "Commerce of the Prairies".