In what way and how well are the characters described? Do they strike you as real-life persons or not? Are there any living persons you know of that resemble any of the characters in Ivanhoe?

Are we talking about the main characters here, or the characters in general?

in general :)

I find Ivanhoe's character believable in that he is well portrayed as the prodigal son, loyal subject, and hardened knight.

I see Rowena in the same way. She's never surprised me, and in the novel acts just as a young noble woman should. She gives up the man she loves and does as her guardian asks; she's supportive and trusting, but above all else (even a bit of argument) she's duly submissive.

Rebecca, I don't think she's believable. A young Jewish girl of the period would not be prone to falling in love with a Christian knight, nor would her father have sat back and watched. He wouldn't have been that naive in regard to his own daughter, especially the ONLY child. Although I do love her father's character, and I'm always refreshed that he is NOT portrayed as a typical money lender.

King John was portrayed in the way of Shakespeare, the poor guy never has a chance........... historically, Ivanhoe portrays little about Richard that we don't already know, and his actions (in such a short time frame) are embellished.