credited with the exploration and colonization of Nueva Vizcaya, the huge area of Mexico which today encompasses most of the states of Durango, Chihuahua, and part of Sonora. With funds provided by his uncle, who had made a fortune in the Zacatecas silver mines, Ibarra, as governor of Nueva Vizcaya, opened up much of the northern frontier of New Spain in the 1560s before returning to Mexico City.