Not to be confused with Native American Nations
Natives are the tribes that live in uncolonized provinces. Natives can influence the chances of a successful colonization attempt, depending on the number, ferocity, and aggressiveness of the natives in the province. Once a colony reaches 1000 population it becomes a full province of the nation colonizing it, and all natives in the province are added to the population.
Depending on the ferocity of the natives, they may attack armies passing through a province. A passing army can also attack the natives themselves, by use of the Attack Natives button on the army's interface. In these ways it is possible for a tribe to be completely defeated. This can significantly increase the colonization success chance; though it also removes the possibility of them later joining the colony.