-Humanity was once a great civilization.
-Struck down by enemies and reduce to fractions of it's former selves.
-Saved only by the will of a single protector.
-Now Humanity is on the rise, rediscovering itself and the universe.
-Still beset by old enemies.
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That exact scenario could be applied to the Lord of the Rings, The Matrix, and I'm sure a dozen other major fictional works. It's too broad.