Why do they change religions?

[unmerged(403441)]

Why do the kings change religions? is it random, or is there any trigger I have not found? For instance, I was playing Leon and got to 1425 with a score of over 40,000 (OK maybe not that impressive but I'm a beginner) and had most of Hispania under my rule when my king had the stupid idea of becoming "Fraticcelli". Within five years game time, most of my dukes had revolted and the Empire, Scotland, Castille, the Papacy and three other countries had declared war on me. My king's grandfather had had the same idiotic idea but I was able to make him catholic again. But with my present king the option was greyed out because he was not zealous. By the time I quit in frustration, the Empire had already grabbed all of the original Leon kingdom and without my acceptance, by the way; the game just decided I had lost that particular war (which was true since I was getting a beating) and I was about to lose everything.
So, is it just random change of religions and I can't do anything?

 

[yezhanquan]

If you're the king in question, then the religion change should not take place without you noticing.

 

[Shadowkire]

The only ways your king can change religion are: influenced before you the player take control of them(guardian's religion) or your spouse or chaplain made an event window pop up asking if you wanted to switch. The chaplain is most common because it is a possible result of the social research mission.

 

[Lorehead]

Sorry, where’s the event where your spouse asks you to convert? I wasn’t able to find it.

 

[unmerged(403441)]

Shadowkire:
Thank you very much, you are right; three generations back I distractedly send the grandfather to be educated by a Fraticcelli. I never noticed it but that was the king I had to change religion. And you are right too, yezhanquan; there was a pop up when he was still a prince beyond my control saying that his father had convinced him to switch, and I never controlled that father because he died before becoming king. And also there were several other pop ups in previous generations asking for conversion, to which I always said no. Thank you for your advise, I'll be more careful next time. It turns out that I was the idiot.

 

[yezhanquan]

Hey, no worries. Maintaining religious homogeneity is one big key in maintaining the realm, particularly if you expand across cultures.

 

[Kaiser Ludwig]

Hey, no worries. Maintaining religious homogeneity is one big key in maintaining the realm, particularly if you expand across cultures.

Actually, promoting religious disparity in your realm is a great way to promote cultural homogeneity with medium (or is it low now) CA, with the free revocation of infidels

 

[Shadowkire]

Sorry, where’s the event where your spouse asks you to convert? I wasn’t able to find it.

I looked, it could be that it was event 39020 "Heretic character attempts to spread the faith" and it just so happened that my wife was the heretic trying to spread the faith to me.

 

[yezhanquan]

Actually, promoting religious disparity in your realm is a great way to promote cultural homogeneity with medium (or is it low now) CA, with the free revocation of infidels

Ah! But, I haven't revoked anyone's titles so far. I'm too soft as a liege =X.

 

[unmerged(403441)]

One advantage I did find with having heretic dukes is that I can call in the Orders to fight them if they get rebelious.