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The very first thing we saw in 1977 at the beginning of a New Hope was "A long time ago, in a galaxy far, far away..." It tells us that Star Wars of course takes place in the past. How long ago in the past does it take place though? At what stage of development were we on Earth during the time that Star Wars takes place?
Moreover, do we even exist during the time of Star Wars? Is there any mention of how long ago in our time Star Wars took place?