You should probably win by today.
On one of those trips, an assassin fires an arrow at the king. He survives, but the arrow was poisoned with a poison unknown to your lands. When interrogated, he reveals that he was sent by the guy in the fortress, now dubbing himself the King of Chasmfiends. The king is still alive, but the poison is slowly killing him.
Howlong will it take to besiege the castle?
From now on, for every day that you are inactive your happiness drops 10%
my king starts traveling around the land telling people of the riches stored away in the castle and how it can be theirs
Your happiness drops to 80%
They are just for fun, so that people can unite because of religion. Sometimes their gods give them stuff, but the "gods" are really just powerful spren messing around.
I pull out all my troops from the rebel island and send them to the castle