I can't help wondering why the family does not come up in history books. Its not that we seem to have held anything of major note since the alienation of Chancellor William's property through his heiress to Godfrey Mure. However at that or about that time there are various grants of property going on which seem to indicate that the Caldwell's were seriously there just under the surface.
I wonder if someone in the family judiciously supported the Wallace or the Bruce or more likely the early Stewarts and jsut happened to swan in to a good connection with some seriusly powerful nobility. Perhaps there was a marriage connection or maybe the wrong side of the blanket subsequently looked after.
If the name is not mentioned perhaps it was a connection where the influence was established through the female line. Another possibility is that they are there and we are looking at them but not recognising. I mean that just as Mure of Caldwell was known simply as "Caldwell" at court then perhaps other have gone down in history from their property name even though they acknowledged themselves as Caldwell's. Only a thought (romantic fool) fire away
Whatever the period of influence must have faded away soon enough - probably when the royal family gave up their Ayrshire connectons for Edinburgh. I also note that Scots history is full of waxing and waning connectons, influence peddling, bands and kidnapping the king (notwithstanding the Presbyterian thing). I have read a fair bit of Scots history and still have trouble getting my head around it - English history is much more straight forward.
Wonderful down here in "Oz" can post all these messages without fear of interruption as everyone else is either sensibly in bed or out equally sensibly doing their work-ethic thing