". . . why do movies always use British actors to portray baddies?"

Liz, I'm afraid I'm in a quandry. What movies are you referring to? I can think of lots of American-made movies in which the villains are all played by Americans. If there were a fair number of British actors in the Star Wars series (e.g., Alec Guinness, one of the good guys), maybe it was because large chunks of the Star Wars movies were shot in England. The whole swamp scene where Luke first met Yoda was on a sound-stage in England.

And what about all the heroes that have been portrayed by English actors? The various James Bonds for openers.

Don Firth