The Force Awakens will introduce us to some new Sith villains for sure, but Darth Vader will always be the most iconic. James Earl Jones was his threatening voice, but the body was an English actor who didn't just gesture around in silence like a mime during filming; he voiced all the lines in a West Country English accent.
Clips of the English actor (and bodybuilder!) David Prowse mugging along to pre-James Earl Jones Darth Vader lines cropped up in this behind-the-scenes featurette ages ago, but it's never not funny. Will the Force awaken awesome accents in the Sith badasses of Star Wars: Episode VII? I sure hope so. [Reddit]