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Why did Europeans thrive so well and branch off into America, Australia, colonies, etc. and most South American/African countries/ Native America remain so underdeveloped for so long?(r/explainlikeimfive)
Also remember that the native peoples of the Americas were annihilated by disease before contact with most Europeans. Seriously 90+% died in the 1500 and 1600s following first contact with the Spanish, all across North and South America. Read 1491: New Revelations of the Americas Before Columbus for more details. Essentially though, the “vast wilderness” of the Amazon rainforest is actually an overgrown garden. The peoples there built on a massive scale, but did so using wood and dirt (no stone in the Amazon). The first Spanish explorers in 1530 or so reported the river lined with cities for literally days on end. It was 100+ years before the next explorers attempted a passage of the Amazon, and by then most of the natives were dead and the cities had disappeared into the forest.
North America has a similar story, with huge population densities lost to disease. The Indians the Europeans encountered in the 1700s and 1800s were essentially the survivors in a post-apocalyptic wasteland, trying to recreate a civilization from the shattered remains of the old while fighting off an invading barbarian horde from the coasts.