“Actually there were, but long ago before the coming of the Portuguese in 1460 and the introduction of firearms.”
“rapidly fell apart with the introduction of European diseases - mainly syphilis. The cities were built from wood and decayed back to jungle in a few short years.”
This unnamed country doesn’t sound very smart to me if they allowed that to happen. Why didn’t they invent firearms or at least something more advanced than spears to defend themselves? MASSIVE FAIL, IMO.
Only massive fail from the modern perspective - at the time the African cities had lots of food, running water, sewage systems and little or no crime - things which did not exist in Portugal. The Portuguese sent repeated requests to be allowed to remain in Africa. Those in power at home were afraid if they were allowed to remain, that many others would flee to Africa and away from the horrid living conditions in the then most advanced civilization in Europe.
They were powerless before diseases before which they had no immunities. They had no need of firearms as they lived a mostly peaceful life and warfare was fought with surrogates - one was chosen from each side, the winner’s side won the argument. Armies fighting to the death was not done - a European invention. This is about civilization, not who has the best invention - by that measure, the Egyptian, the Greek, and the Roman civilizations were massive failures