From BattleMaster Wiki
"Kings are elected?"
- "Oh, absolutely! Lots of them prattle on about 'divine right' and so on, but when push comes to shove, every one of them is chosen by the nobles of the realm. Now, different realms do things differently. Kings and Dictators only get elected when the old one abdicates or is incapacitated. Other realms call their rulers 'Prime Ministers' and elect them every month.
- "Rulers aren't the only elected positions, either. Some realms elect their Judges, or even their Generals! And of course, votes count differently in some realms than in others, giving more weight to Dukes, for example. Some realms may have unofficial votes for other positions by using 'referendums'. The results of these referendums aren't necessarily mandatory, but they can help the king or whoever make a decision."
(See elections for a thorough discussion of what triggers an election, and how exactly the voting system works)