There are lots of computer games of medieval strategy which are not just about fighting but about building communities and expanding kingdoms though diplomacy and trade.
A word of caution: for your own e-safety play these offline or, if online, then only with people that you personally know and with your parents’ permission.
Our top recommendations for teenagers are:
- Medieval II: Total War from SEGA
- Mount & Blade: Warband from Paradox
- Anno 1404 from Ubisoft
- Crusader Kings 2 from Paradox
- Age of Empires II HD from Microsoft
You can see two reviews of these games here.