Okay, so I've decided to try and lend some help (in some of the little free time I have) to some of the good folks over at the Paradox Interactive mod forums, and see if I can't scrounge up some good data regarding East Africa during the Middle Ages. Only problem is, its incredibly hard to find much of any info on the region (for multitudes of reasons), as its a region of the world that holds a bit of interest for me and its currently almost completely untouched in the nifty mod in progress that'll expand the game to include the entire Old World. I know the basics, like the major players in the area, the religions of respected civilizations, ect... but its pretty bare bones. Does anyone happen to know a good resource for some reliable information beyond "Great Zimbabwe was in present day Zimbabwe!" If nothing else, it'd just be fun to have a new corner of history to learn a thing or two about. At best, maybe I lend a hand towards a potentially awesome gaming experience.
Posts
http://en.wikipedia.org/wiki/Great_Zimbabwe
Some that look promising are
http://www.sciencedirect.com/science/article/pii/S0278416508000585
http://www.jstor.org/discover/10.2307/3889086?uid=3739616&uid=2&uid=4&uid=3739256&sid=21101047802913
I haven't read these, but they're scholarly articles about its history, culture, and decline.
The PDF are behind a paywall, but that's research for you.
You may find other cites that aren't or whatnot.
Of course this also depends on how you define 'Middle Ages' and 'East Africa' ; a lot of the coast, for example, was heavily populated by the Portugese ~14/1500 , and is likely to be thoroughly covered in their sources for the period. On the other hand, the history for the area off the coastline and prior to ~1200 is (or certainly used to be) remarkably opaque, due to a lack of written records.
Goodreads
SF&F Reviews blog
For authoritative sources, UNESCO came out with a detailed history of the continent. Alternately, I just mentioned the existence of the "Journal of African History."
Is Sundiata too early for your purposes?