In the sense that he is a physical human being, yes....but he's anything but "real". There's not one damned thing about him that is "real".
Do you realize that we know far more about the life and background of the fictional Darth Vader than we do about our own "real" President of the United States?
Let that sink in for a moment.
I think Barry is more like Emperor Palpatine. Darth Vader got religion at the end.
You are exactly right about his background, however such knowledge does exist, people are simply looking in the wrong places.
His history is found within The Bible and such works as Paradise Lost.