High Count vs. Low Count
One of the critical issues surrounding the the land that would one day be Texas at the time of European contact is grappling with the population of the Americas in 1491. If few people lived in the Americas, then the lands discovered were in fact a pristine wilderness, echoes of a more prosperous time.
If, as some believe, perhaps hundreds of millions inhabited the Americas before Columbus, then advanced and methodologically sophisticated Indians likely heavily modified this region into the landscape described by the first Spaniards to cross it.