I think the format for all this is very important to determine just how useful it would be to people. I think what people would want is a general set of "stats" (not as in game stats for a specific system, but a rating of their strengths and weaknesses in things like charisma, leadership, military capacity, physical ability, intelligence, etc), a BRIEF history, and some extra details that are interesting (as in, perhaps not common knowledge to all) and USEFUL for rounding out the individual as an NPC in game.
In other words, you want short, sweet, and lots of it. And of course, each "era" would benefit from a point-form timeline of major events.
I'd be willing to handle any era of Imperial Rome. I'd leave Republican Rome to someone else who was more qualified in terms of either academic credentials or amateur passion.
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