I'm not sure how to define this, other than look at the Bronze age collapse, the fall of the Western Roman empire, and post-contact people in the western hemisphere. So given those three examples, how many more have there been? I can't think of any other examples of the near total destruction of an established society, services, and trade

Edit: I guess the word in the way I'm using it would best be defined as the total or near-total collapse of an established society. In the Bronze age, as far as I'm aware, almost all societal progress was undone, to the point that we literally lost the ability to read and write. In Rome, it was more or less cities and villages left to fend for themselves, there was no system keeping everyone together and protected. In post-contact America, the population was nearly wiped out, with empires being completely demolished by invaders, the survivors living in scattered groups.