Then I would probably assume that 9,000 years ago there was a prophecy that humanity has forgotten about. Prolly something like:

When the Lord of Imbeciles rules the Empire of Eagles, and in violating the flesh of the children of men, unbound from law by dark pact and oath, banishes justice from the land, Those Forgotten will heed screams of pain and rage of innocence sundered an so bid the Mask of Zuul rise from its place 'neath ancient ash, an seek out Keymaster, he whom upon donning the Mask will break free the truth of the heavens, and lay bare the God, aloft in sight all along, his nature locked from mortal eye in shell of illusion since millenia 'fore history of man had begun, to the eyes of the world. Nanna, Sin, Gozer. God of Wisdom, Omens, Justice. The True God of the Moon. The God of Judgement, come in his time, to judge all world, for all world's dark crime.