Olympia is Wonder Woman's counterpart from the anti-matter/Earth-something universe, a reality where villains always win and they pretty much rule the world. In the comic books the counterpart to WW is Superwoman, but in the animated movie Superwoman seemed to be the counterpart to Mary Marvel, which made her all the more creepy.
(formerly Anon, still Librarian)
"What is the point of having free will if one cannot occasionally spit in the eye of destiny?" ("Gentleman" John Marcone)