Speaking of civilizations that were great in their day but then vanished to be forgotten or anyway dismissed as mere fantasy--I wonder what it would take to do a
Terra Preta-wank?
I'm not being too serious since the article on
Terra Preta itself reminds me the whole civilization complex does not arise until 450 BC, pretty far behind Old World foundations as New World ones generally are, and also any American civilization shares the liabilities of others--no domestic animals of any great significance, hence limited transport capabilities, limited disease pools meaning low resistance to Old World disease, etc.
But even OTL it's an example of an entire civilization complex we know now existed, but scholarship had completely forgotten about as late as the 1980s and my first try at college. Lost cities indeed!
Now supposing for a moment that the timeline of development of this system of exploiting the potential biomass of the Amazonian rainforest had indeed developed some thousands of years earlier--certainly there were human beings living in South America most of 10,000 years ago, and there was perhaps time for these people to be among the first to develop systems of agriculture rather than the last. (Indeed a book referenced in the Terra Preta article, 1491, is a book I have and it discusses quite a lot of Native American activity going much father back than is generally realized, including in South America, and even suggests that the "natural" ecosystem of the South American rainforests has been heavily manipulated by human activity, to make a very large proportion of its "wild" plants useful to humans--that would have predated Terra Preta civilization proper). They might not have draft animals (though perhaps some South American jungle fauna are candidates for domestication) but anyway they do have access to the vast river network of the rainforest, and so we can imagine them developing river navigation quite a lot, and perhaps even, at the mouth of the river, venturing out onto the Atlantic, up and down the coastline, and perhaps even learning to cross it to Africa.
The upshot might be a precocious ocean-traveling civilization that founds successors in West Africa and the Congo river basin. Conceivably they could rise and prosper only to foster an early start to the Eurasian complex of civilizations, leading to the consolidation of the many Eurasian disease pools into one supercontinental system of endoparasites--bringing those plagues to western Africa and thence back to the South American homeland, where the population would be significantly more vulnerable to these diseases and might, much as OTL, suffer so much depopulation they drop below the threshold needed to maintain their agricultural system and thus as per OTL vanish from history.
It would be a significantly different world from ours, with a lot more Classical era civilization in contact with the Med and Near East located in western and central Africa; those peoples would probably also suffer demographic collapse but bounce back better than their American mentors and even if we counter-butterfly so that Rome and all that happens much as OTL, and an expansionist Western Europe develops around 1500, they find the Africans harder to dominate than OTL. (Still, they might manage to negotiate terms with various coastal African powers, and thus circumnavigate Africa and proceed much as OTL in the Indian Ocean).
Would South America then fall out of contact with Africa and remain collapsed, or perhaps build itself up to OTL 1500 levels, only to be knocked down again by another wave of Eurasian disease brought by the alt-Iberians? Or would the Africans remember their trans-Atlantic inspiration and colonize it, creating a new trans-Atlantic jungle-based civ that is much more of a challenge to the Europeans?
The former fits the "Atlantis" style narrative a lot better, and might be plausible if the Eurasian disease wave is devastating both to the Africans and Americans, to the point that the arts of trans-ocean navigation are totally lost and not recovered.
To be sure--despite how very devastating Eurasian diseases were to American populations in the early modern period, it is rare or perhaps unknown to see a society utterly wiped out by disease alone; the falls of civilizations to disease are generally matters of rendering them hopelessly vulnerable to conquerors (the same folks who brought the plagues in the first place) and without such interlopers to administer such a coup de grace and then take over the land and surviving populace for their own purposes, probably even a disease that killed 90 percent or more of a people would only cause an interregnum, perhaps lasting centuries, but the arts of civilization would probably not be totally lost. Even granting that much lower populations both deprive the people of means of labor to maintain a given level and take away most of the incentive to do so, eventually the population will recover from survivors and both the ability and need to cultivate more intensely would recur.
If we can time things so that the latter point is reached around 450 BCE, the upshot might be a situation in South America that resembles OTL.
Still don't know what to do with the more advanced Africa though!
