I know that Dreadfort reads "when you play or take control of a House Bolton Character…draw a card" and I know that in AGOT the term play is short for play from hand.

I am more curious as to whether you control your discard pile/dead pile in the same manner as you control characters who are in play.

Is Control an in-play only condition or does it extend to all cards I own? That is assuming that they are not explicitly under the control of my opponent via card effects?

In particular, I am wondering if I bring a bolton character into play via The Kindly Man response will i be able to draw a card?

I think taking control refers only to the cards in play (with logic being that you can take control of something if you can take it from someone. And cards in discard/dead pile are technically not controlled by anyone). So Kindly Man doesn't trigger Dreadfort.

If control were an "in-play" condition only, there would be no need for Kindly Man to specify that the card comes into play "under your control." All cards owned by a player are considered to be under that player's control, whether the card is in-play or out-of-play, unless otherwise specified.

So, if you use Kindly Man to put a Bolton character into play from an opponent's discard pile, you have taken control of it (and The Dreadfort could be triggered). But if you use Kindly Man to put a Bolton character into play from your own discard pile, you have not taken control of it because it was yours to begin with - and The Dreadfort cannot be triggered.

(If putting something into play included "taking control" of it, The Dreadfort would not need to include "after you play" because the "after you take control" part of its play restriction would include the "after you play" part.)

Of course, don't forget that cards and effects only interact with cards that are in play unless they specifically say otherwise. So "choose and discard a card controlled by an opponent" does not let you target a card in the opponent's hand, deck, etc., even though the opponent does "control" those cards.