Search function, mayhap?
-.-
There are at least one-and-a-half problems with the (regular) claimant quest:
1) You can't assign fiefs to lords, hence castles and towns do not get garrisonned while the civil war rages on;
½) You can't complete the quest. I'm marking this (only) as a half because I remember reading someone on this forum saying it had worked fine for them. I (and a few others) sure as hell couldn't complete it, however. End dialog was bugged -- claimant became King, but quest remained in my notes. Will probably autofail after a while; haven't yet played long enough since then, though.
-.-
With all this being said, with the 1.12x patch coming any decade now, it might be the best just to wait for that.
Hold on -- the patch actually fixes that issue, right? Right?