The Reconstruction of the American Southwest

I lean towards a volcanic event of some kind or several. It's almost like newspapers, west of the Mississippi didn't even really come online until the 1840s. The entire American Southwest was buried in at least one, maybe two, maybe three events. And we're dealing with each cultural layer, getting more advanced. Of all phenotypes living in absolutely monstrous cities. To which they have almost no understanding or history of these people.