The original Vader concept in Star Wars..
If you try really hard to forget that Empire Strikes Back etc were ever made and Lucas did not decide to make Vader and Luke's dad the same person, you really can get the impression of the kind of dark medieval knight that Vader was inspired by.
Vader is the sort of fanatic henchman and opportunist that is the most sinister enforcer of the corrupt regime who is potentially the most dangerous threat to the good guys but in the final battle either finds himself conveniently placed to avoid capture while his masters are not so lucky, or at the height of the battle their horse is spooked and bolts from the battlefield with him in the saddle or dragged away hanging from the stirrups.
Peter Cushing would usually play that role as the duplicitous black knight or the Saracen ally of a cruel ruler.
The massive success of Vader's costume and sound design though clearly undermined any notion that the implacable, monolithic villain could possibly be dismissed in that way. Lucas realised he was stuck with him so he might as well expand his part and enhance his status.
"Who can't use the Force now?! I can still use the Force!" - Yarael Poof