In some regions the indigenous peoples created monumental architecture, large-scale organized cities, chiefdoms, states and empires.
The Portuguese and Spanish equivalents to Indian, nevertheless, could be used to mean any hunter-gatherer or full-blooded Indigenous person, particularly to continents other than Europe or Africa—for example, Alaska was a glacial refugium because it had low snowfall, allowing a small population to exist.
Some of these civilizations had long faded by the time of the first significant European and African arrivals (ca.
late 15th–early 16th centuries), and are known only through oral history and through archaeological investigations.
) for the indigenous inhabitants, which implied some kind of racial or cultural unity among the indigenous peoples of the Americas.
This unifying concept, codified in law, religion, and politics, was not originally accepted by the myriad groups of indigenous peoples themselves, but has since been embraced by many over the last two centuries.