In the past I have covered the collapse of a number of empires and societies. We have included the Wari other Andean Empires the wide spread collapse in the ancient Mediterranean, Rome, Medieval Zimbabwe, , Mississippian Cahokia, and the much more recent economic collapses of Argentina and Soviet Union. I have tried not to just pick the obvious ones, because every discussion of collapse seems to center around Rome, the Maya, and occasionally the Anasazi of what is now Southwestern United States get thrown in if you are big Tainter fan.
But there are many many other societies, empires, countries, etcetera that where out there, and no longer exist. Or at least exist in a very different form. My purpose in going over all these lost empires is to simply exhibit how many powerful countries, that appeared to have an authoritative presence, are simply no longer around. If you really get right down to it, cannot really be surprised that small marginal colonies like Easter Island and Nordic Greenland are gone. But these are all pretty large societies. And in some cases, not only are not only gone, but they are gone almost without a trace. They were only found when archaeologists started digging up their ruins.
I have not done any of them for a while because I got hung up on a fairly complicated project that will follow this post. It is complicated because we actually have better records of it in some cases, and with better records their is the inevitably more nuanced collapse. In this case it belongs to a series of global collapses that spans at least three continents: Asia, Europe, and North America. It is the collapse that ended the Classical Historical Period and brought in the Middle Ages in Europe.