The population of the New World prior to contact with Europe in 1492 is the subject of debate in historical and archaeological circles.
One extreme, some people assume that the Americas were only sparsely settled, largely by primitive, nomadic peoples, and that most of the New World was virgin wilderness. They estimate that five million or less humans lived in the Americas at the time of Columbus' landing.
Other scholars are advancing a contrary view, that Pre-Columbian peoples built cities and practiced large-scale agriculture, enough to support a hundred million or more. The largely empty, supposedly natural continent European settlers of North America saw had actually undergone a recent development after the bulk of the indigenous population was killed off by European diseases that traveled well in advance of settlers.
While population estimates for certain specific areas of the Americas can be based on archeological data, such data is insufficient to form credible population estimates for the American continent as a whole, so projections rely in part on conjecture and continue to vary significantly.