A free mod for Mount & Blade II: Bannerlord, by Tanj.

This mod adds the choice to retain control of a fief after capture.

A fief that you conquer will be included in a vote for ownership of the kingdom. The vote will be called the next morning, and you will see the “menu” inviting you to make a selection.

If you are the monarch of a kingdom, you can assign the fief to either yourself or one of your clan chieftains.

If you don’t rule a kingdom but have some clout to spare, you can keep the fief (influence set in config).

The config and log file for the game will be created when the game first runs.