In 1572, Viceroy Martín Enríquez de Almanza, he commissioned Carvajal a captain, sending him to open a road through the mountains between the Pánuco and Mazapil.
Among the privileges granted to Carvajal by the king was that he could recruit, in Spain, up to 100 males, sixty of whom should be married, to be the first colonizers of his Nuevo Reino.