How is a new ruler selected?

[Earl Grey]

What actions influence the selection of a new ruler when the old ruler dies?

I've had a really useless king (4-0-1) for a long time now but he's getting old and his health is getting worse. His older brother (7-3-3) was assassinated at 18 commanding his first army. His only son (3-9-3) he killed himself due to an event.
This royal bloodline has not been good to our kingdom.

Elsewhere in the kingdom there is a very good general (9-4-7, 47 yo) I'd like to see as ruler. How can I improve his chances of becoming the next ruler?

 

[unmerged(96825)]

I think popularity, charisma and personal wealth are the main factors. Probably family prestige as well, and maybe certain traits. But tbh I haven't quite figured this out. I try to help the careers of my best guys but I still get some very mediocre rulers.

 

[icon41gimp]

Check the ledger to find other people in the same family as the king, I think they will have priority. Beyond that I don't know, I've seen some pretty awful characters get selected.

 

[Earl Grey]

His sister became queen when he died. They have no more siblings and no living children or grandchildren. I wonder if the dynasty of crappiness ends with this queen or if it gets passed on to branches related by marriage?

Shortly after the old king died the general I had groomed in battles for 4 decades died, twenty years younger than both the old king and the new queen. Sad.

The question is how many of the royal family you need to have assassinated to ensure some decent character gets a chance at being elected.