As Robert explains in this post, we're trying to forge a Q&A site about Islam (the religion) rather than about subjects of interest to Muslims (the people).
As for Islamic history, it seems to be a bit less defined how much of it would be "about Islam (the religion)". Obviously there have been significant historical events in the Islamic world which have influenced doctrine and practices (the whole Sunni/Shia thing, for example), but there's also a lot of history which isn't really "Islamic history" so much as "history which involves Muslims".
The following post, to me, seems to be in the latter category:
So the question I lay forth for the community is thus: Where, if anywhere, is the line between Islamic history that is on-topic, and that which is off-topic?
(Note also that there is another Stack Exchange site—appropriately named history.stackexchange.com—dedicated to answering history questions.)