Cahokia is close to where I live and a very interesting place to visit.

instead of being violent, inhuman savages who were almost all killed for self-defense by very nice "god-fearing" white folks.

That is an enormous structure we can see in photographs. It should have been so important to know more about it as soon as the invaders showed up, just like all the other amazing structures which have been ignored so very long.

It's about time the self-announced masters of the universe took a good hard look at themselves and start looking for the perspective they've lacked since childhood.

Surely hoping somehow more can be learned about Cahokia in our lifetimes. It would be wonderful to visit.

Of course, people don't just "vanish" from the face of the earth when a civilization declines. They relocate in groups if the region is no longer habitable and take their cultural customs with them, adaped to fit their new circumstances. Or, they stay in the area in smaller groups and keep some customs while adopting new ones.

Or, as in the case of Britain, the original nation remains while its governing control over remote regions declines, leaving behind its influence in those regions.

Various cultures and their influences rose and fell in the Americas, too, before Columbus, and adapted in various ways after him.