2 page paper on African studies

I’m studying and need help with a Psychology question to help me learn.

Please describe some factors that led to the rise and decline of the Aksum (aka Axum) ancient Kingdom in Sub Saharan Africa. Aksum(Axum) reportedly was one of the earliest known civilizations to mint coin for their economy, had a large literate clergy & bureaucracy , and was one of the first nations on earth to make Christianity its state religion during its height. If the Greek traders & visitors, the so-called fathers of Western Civilization, mentioned that this was one of the (5) greatest civilizations during their time along with China and India, how was it possible for this Sub Saharan African civilization to get lost or ignored even into Modern times?

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