Rules that handle Kingdom Management

[Arnwyn]

My preference is Eden's Fields of Blood: The Book of War (which, while the title is a bit misleading, is heavily about kingdom management).

Others (that are known to be at least semi-playable):
- Mongoose's Book of Strongholds & Dynasties
- D&D Rules Cyclopedia
- Expeditious Retreat Press's Magical Medieval Society: Western Europe