This is a quick and dirty kingdom management guide. I used the Civilization computer game as inspiration for a lot of this.
It isn't as complex as some books I post but it fits the needs for my own campaign. Maybe you'll find a use as well.
This guide helps PCs to start their own kingdom and, without micro-managing, gives the basics to building, expanding, and running anything from a hamlet to an empire. There are references for terrain types, features of terrain types, and possible resources available. Once a community is established, there are guides to building improvements ranging from Farms to Colosseum. From City Walls to Castles.
Manage the amount of Food, Commerce, and Production a community generates and grow to greatness or fall to ruin.
Included is a basic system for mass combat when/if you build armies. Starting with the Green inexperienced footmen, to Veteran Horsemen, to Elite Calvary. Special unit upgrades including Ballista Units, Catapult Crews, Battering Ram expendables.
This is in no way exhaustive so feel free to add/modify/delete whatever you like.