Tired of building up new kingdoms each time you change your ambition? Miss your Royal Family, hoping that some day your heir would rule your kingdom with a new ambition? Follow these steps and you'll find yourself using your first kingdom for any ambition that you want.
The only bad news is that you can't do this if your kingdom already ran out of Quest Points. If you have a backup of your kingdom where there are still QPs (and thus, available quests to complete), then congratulations, you can do this.
EDIT: You can actually play too if you already ran out of QPs using the cheat "showallvalidquests", and everything will work fine, but you won't be able to earn Kingdom Points. There's no XP either, but you will gain XP by completing quests.
1) Play your kingdom until you ALMOST run out of Quest Points (not to be confused with Kingdom Points; KPs). This is really important, please do not run out of QPs. Save and quit your game.
2) Go to your "My Documents\Electronic Arts\The Sims Medieval\Saves" folder.
3) Create a "Backup" folder and copy there your kingdom save game (let's suppose it's named "Kingdom1"). In our case it will be a folder named "Kingdom1.tsm" with 3 files in it.
4) Run The Sims Medieval again and complete the New Beginnings ambition by spending all your remaining QPs.
5) Tadaa!! Now you have new ambitions to choose. Choose any and start a new kingdom.
6) As soon as the new kingdom loads up, save the game and name it whatever you want, we will call it "Kingdom2".
7) Quit the game and go again to MyDocs\...\Saves folder.
8 ) You're now supposed to see 3 folders: Backup, Kingdom1.tsm and Kingdom2.tsm.
9) Open Backup and you'll see Kingdom1.tsm (which is a previous stage of the original Kingdom1.tsm in Saves folder). Well open Kingdom1.tsm (the one in BACKUP, NOT IN SAVES folder) and copy the file "WorldCastle_0x00000000.nhd".
10) Now go to Saves folder and open the folder "Kingdom2.tsm" and paste it there.
11) It'll ask you if you want to replace the file, click YES.
12) Load The Sims Medieval and... VOILÀ!!!!!!! You are now able to play your very 1st kingdom with the new ambition you selected!!! And you'll say "Oh well thank you, but now I have 1 QP, I can't play!!". Yes you can, just:
1) Enable "testingcheatsenabled" in your "C:\Program files\Electronic Arts\The Sims Medieval\GameData\Shared\NonPackaged\Ini".
2) Right click "Commands" and click properties. Tick off "Read only" if it isn't already and click accept.
3) Now open "Commands" using WordPad and you'll see "testingcheatsenabled=0". Change "0" to "1" and save.
With this enabled, once you're in the kingdom, you can open up the cheat box (CTRL+SHIFT+C) and type in "setqp (number)", making you able to set as many QPs as you wish in the kingdom. For example, if you're wanting to play as legit as possible, you'd type: setqp 50
You can repeat this process as many times as you want whenever you're wanting to change ambition. But remember, it is extremely important to not run out of Quest Points.
If you're going to post this on any other site please quote and credit me. Thanks and have fun!