Don't count on the Zulu showing up, like Denmark and the Vikings, Firaxis has shown that maybe they will consider another Civ from the area than simply following tradition (though that being said it will be most likely in the game)
In contrast to the Vikings, the Zulus are
the traditional civ for Civ (odd as that may sound) - they've been the representative of sub-Saharan Africa for the first three civ games (even if undeservedly so, given all the other great African civs), and they and their evil warmongering madman warlord Shaka are iconic to fans of the series.
Anyhow, I posted this in the other thread, but I suppose it's relevant here:
Kongo seems like a plausible choice, given that it's been floating around the community for a while, its relative power and influence in central Africa during the early modern era, and the fact that "Kongo" is a recognizable word to the average person (not the best reason, but still).
The
Swahili would also be an interesting addition in my opinion, given that they fit well into the theme of trade routes, though the only drawback would be that similarly to Italy they do take up quite a number of potential city-states.
Nubia would be a great addition in my opinion, as it wasn't merely a southern clone of Egypt, but I see it as unlikely as it wouldn't really work in a Scramble for Africa scenario.
The
Berbers are my personal favorite pick for an African civ after the Zulus, as they have a unique culture and history distinct from that of the Arabs, not to mention there is really a lot of things they could specialize in (maybe religious tolerance of some sort harking to the Moorish years, or the high level of learning as well, or maybe some sort of Barbary Pirates thing, or perhaps a focus on the Saharan trade routes - there's a
lot of possibilities), not to mention they could have a female leader (Kahina). Unfortunately for the average person they'd be too similar to Arab so I suppose their inclusion is unlikely.
Benin is another possibility, though I don't have to say much on them, other than perhaps having the Dahomey Amazons as a UU would be cool.
The
Hausa would be interesting, in my opinion, as they are often overlooked despite their prominence in West African trade routes and so forth, but unfortunately I think they might be seen as too similar to Songhai.
Kanem-Bornu would be in a similar situation to the Hausa.
The
Maasai might be possible too, given that they're pretty well known to the average person, though I think it'd be a questionable choice given that they did not develop the sort of urbanized societies the "civilizations" in Civ represent.
There's also
Zimbabwe, which I think qualifies more as a civ (with a traditional definition of that) compared to the Zulus. Still, there's too much overlap with the Zulus, so it's either Zulus or Zimbabwes, and the former is almost certain.
There's also some of the other West African coastal groups, like the
Ashanti and
Yoruba, who played an important role in the Atlantic slave trade - unfortunately this might be too controversial an issue to have these civs capitalize on (imagine a civ with an "enslave and sell slaves to
European other civs" UA).
Let's see... well, that's all I can think of within the realm of possibility. There's others like some of the more developed states in Angola and the Kenyan/Tanzanian highlands but they aren't as well-known.
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Personally, though, I want the Berbers, because I think they're really cool and awesome and all that. But probably won't make it, as they're seen as too similar to the Arabs.