Two questions about the use of real people in fiction. Check 'em out. Click here for an archive. So all other things being equal, always go for historical accuracy. If you can, make sure the Gordons you mention in your story are in the right part of Scotland.
Fashion is all.
Those who don't care won't notice one way or another, and those who DO care will not send you angry letters. This will impose a healthy discipline on an author, as it saves us from a lot of temptation to move families and even countries around at our convenience. I'm not the only one who learned a lot more history from novels than I learned in history class. That means we really have a duty to readers who expect that we're presenting history as truthfully as possible. Of course, the reader isn't an idiot.