Here is the full list of all 19 Fit For a King achievements.
Fill your jail with prisoners.
Ordain the bear.
Meet your rival at the summit.
Outspend your rival at the summit.
Make your rival cry.
Reform the church.
Meet the leader of a distant land.
Play an anachronistic song.
Marry a princess.
Ride a horse.
Get an evaluation of your rulership.
Fill your chamber with spouses.
Marry an inanimate object.
Have a swashbuckling adventure.
Get a suit of gold.
Get a suit of gold for a monkey.
Gain 5xp.
Get assassinated.
Conquer the known world.