 But Spanish conquests in the Zapotec and Mixtec regions of southern Mesoamerica were relatively rapid.Outside the zone of settled Mesoamerican civilizations were nomadic northern "indios bárbaros" ("wild Indians") who fought fiercely against the Spaniards and their indigenous allies, such as the Tlaxcalans, in the Chichimeca War (1576–1606).The northern indigenous populations had gained mobility via the horses that Spaniards had imported to the New World.