In Kingmaker, the map is divided up into estates. There are two kinds of these territories: village estates, and castle estates. Village estates can be purchased by spending honor points, which you earn by "living like a lord." So when you do things like hold feasts and jousts, have a wife or attend church, you earn this new resource called honor.
When you add a new estate to your empire, any resources created by that territory get sent back to your main castle via a carter (sent from a Carter's Post, one of the new buildings in Stronghold 2). Smaller village estates are quite useful for setting up external farms, leaving the space within your castle walls free to be used for your war making apparatus. Castle estates are huge structures that are equal to your own, initial castle, and must be taken by force.
So in Kingmaker, you will fight for complete domination of a map, acquiring and losing territories as you fight it out with either computer-controlled or human opponents (up to eight people can play in Stronghold 2 multiplayer matches).
The other new component of Kingmaker is the ability to spend your honor points on promotions. Promotions are Stronghold's take on the "ages" concept from other strategy games. You begin the game as a lowly Freeman, but can advance through the ranks up to a Squire, Knight, Knight Errand, Duke, and eventually become a full-fledged King. Advancing in ranks gives you access to new buildings and units, but where Stronghold 2 differs from other strategy games is that your existing units stay the same.
So in other words, an Archer created by a Squire is the same as an Archer created by a King. So if you want to stop spending your honor points on promotions early on and instead concentrate on acquiring more territories and building up a huge army, you can opt for that instead. It's entirely up to the player.
Territories and promotions will be available in both the regular campaign and Kingmaker mode. The primary difference there is that in the regular campaign, you can't advance any higher than Duke, as there already is a king (and he's perfectly happy in that role thank you very much).
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