Suppose you were a successfully published writer who had a well developed, and well liked, main character. But a problem arises: you want to put that character in a different century and in a different social/ethnic/cultural background in order to solve a crime.
A major problem. But what do you think of this idea? You put that character in that setting and you give the character all the traits (and perhaps a few more) of the one already established. But instead of calling him 'Jon Champion' you call him 'John Rogers Champion.' You make your historical character the great-great grandfather of the current character.
Why wouldn't it work? Character traits run in families through genetics. Why not this? What do you think (and has this ever been tried before?)