looking for a science fic.book

[alice]

Got an old science fiction book from used book store. Story was about a group of "knights" that kept order over several worlds.  The head of the "council" was from a certain family notable for their bright red hair and special mental powers.  One knight betrays the others at a council meeting, ambushes them and has them all killed.  Only himself (the bad guy) , a young woman knight off on another planet, an old retired knight, and the heir apparent, escaped.  The now orphaned heir is taken by the woman to be raised by the old hermit on an obscure planet (hopefully no one will notice his red hair)until he matures and can be trained by the old man in the way of the knights.  (Sounds familiar, doesn't it?)
After remarking on the similarity with Star Wars and wondering if Lucas got his story from this one, I returned the book which has since disappeared.  I believe it was written in the 50's or 60's but am not certain of that.
Any help would be appreciated.  Thank you very much.  Alice Simmons