"Poetry" versus "History" in Aristotle's Poetics

Why does Aristotle seem to take such a narrow view of "history" when contrasting it with "poetry"? I shall revisit his notions of "poetry," "history," and mimesis to clarify the contrast between declarative assertions central to history and mimetic displays of "universals" central to poetic fiction. The key difference lies in their treatment of individuals. While history affirms biographical facts based upon evidence, fiction illustrates types of characters in types of situations, as delineated by Aristotle in his ethical writings.