I saw some people who are not aware of this feature. Here some more info:
KNIGHTS
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Knights can be assigned to specific roles in which they are able to boost specific functions of your city. They are also needed to lead your troops into battle.
APPOINTING KNIGHTS
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When you click on your Knights Hall you will be able to appoint your own knights. Each role can be filled by only one knight but can be re-assigned at any given time without any costs.
Once you have appointed a knight you will see the following window under the "My Knights" tab. Your knights will gain a set amount of experience on an hourly basis depending on the level of your Knights Hall.
Here is an explination of what you see:
Unassigned Skill Points: You can use these points to raise your knights;
Politics: Needed if your knight is assigned the role of "Foreman".
Combat: Needed if your knight is assigned the role of "Marshal" or is one of the knights leading the troops.
Intelligence: Needed if your knight is assigned the role of "Alchemystic".
Resourcefulness: Needed if your knight is assigned the role of "Steward".
Current Role: Can be either a role or if idle can be used to lead your troops into battle.
Increase XP: You can use items to boost the experience of your knight;
Train with Kay, Galahad or Arthur
Boost: You can boost your skills by using items temporarily for 7 days:
Rose of Charisma, Gauntlet of Courage, Mirror of Knowledge and Gloves of Gathering
Assign Skill: You can assign the unassigned skill points you have by clicking here.
Assign Role: If your Knight is idle, you can assign them a role here, you can also re-assign and un-assign roles in this tab.
Dismiss: You can remove the selected knight from your active knights. Doing this will result in the loss of all experience gained and you will no more have to pay the salary of this knight.
ROLES
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Foreman
The Politics score of your Foreman increases the construction speed of your buildings by 1% for every 2 points of Politics.
Marshall
The Combat score of your Marshal increases the training speed of your troops by 1% for every 2 points of Combat.
Alchemystic
The Intelligence score of your Alchemystic increases the speed of your research by 1% for every 2 points of Intelligence.
Steward
The Resourcefulness score of your Steward increases the production of resources by 1% for every 1 point of Resourcefulness.