I've been reading up on pre-Athenian democracy (sometimes referred to as primitive or tribal democracy) where leaders were selected by some or most members of a group and were subject to established rules in order to retain power. Benjamin Isakhan and Christopher Boehm in The Edinburgh Companion to the History of Democracy refer to tribes oscillating between despotism and democracy due to participatory mechanisms. (12) A consensualised group decision process is also mentioned (36) with egalitarian features are mentioned as a balance against a leader becoming too powerful.*
From anthropology, translations, and political science, there seems to be a growing academic basis for the Dorians, Phoenicians, Assyrians, and Vedic-era Indians engaging in some form of democratic procedure or at least a limited oligarchic system before the Greco-Roman era.
Are there any instances of something similar in sub-Saharan Africa be it a migratory group, a smaller tribe, or merchant city where there was power sharing and some kind of input from citizens?
The definition of "democracy" used today is generally "whatever the US state department labels as a democracy". Hunter gatherer groups usually practiced some sort of democracy, but this isn't considered "democracy" in the academic sense because there is no state.
If you are interested in looking into these sort of loose federations which operated on democratric principles there are several examples, such as the Bhagdana and Nok cultures. I direct you to: