The reason for this is that in the event file, there is a mistake in the code! It says religion = christian. Which does not exist. There is no religion ...
Must not be Heretic; Must not be Excommunicated; Holy order leader must have 300 wealth ...
Every Holy Order in the game will have its own society once they can be hired.
In vanilla CKII, this only applies to the Christian, Muslim and Israelite religion
Unless I find another solution which doesn't require editing an existing CK2 file, this issue
From Viking holy orders to a restored Roman Empire, here's how they pan out in. ... A Norse Pagan warrior brotherhood that functions as a Holy Order in CK2, the Jomsvikings
Mercenary armies select a name based on their culture, as shown in the table
CK2 Decision IDs · Convert to Liege's Religion · Convert Religion · Convert Culture · Convert to Liege's Culture · Convert to Local Culture ([Root. Capital. Culture.
In the 1983 Code of Canon Law, "The Latin words sacerdos and sacerdotium are used to
CK2 Blog. The Byzantine Empire and the Holy Roman Empire (if Byzantine