Vassals who have a liege of a different faith are unable to wage holy wars. Based on the way the CB is written up I'm sure thats the way it was designed. So that bit isn't a bug.
I thought it's only that they're unable to wage holy wars against people of their liege's faith? So a christian count who is in a muslim realm can infact wage holy wars on pagans for instance.
Lets take a look: (all of the below must be true)
-You can't be pagan
-You can't declare a holy war on someone within the same realm
-In order for it to be valid, the target has to be one of the following, a heretic compared to your faith (catholic vs lollard and visa versa, not catholic vs orthadox though), or from a different religion group, or you're a muslim and they're a different type of muslim (the target of your attack must not be at war with non muslims)
-You can't declare holy war if your liege is not from the same religion group as you
-You can't declare holy war if your liege is the (exact) same religion as the one you're targeting
-Your liege either has to be the same religion as you, or you and your liege are both not heretics.
Any questions? P.S. My brain now hurts
Examples:
For the sake of all examples assume crown authority is set to autonomous vassals and all other non religious factors aren't present.
[EDIT!] List outdated, some of these examples are wrong, see below
-You are the tribe of lithuanians(a pagan duke), you're attemping to declare a holy war, it's not going to work
-You are an orthadox greek duke declaring a holy war on a monophysite duke in the byzantine empire(ruled by an orthadox emperor), it's going to work
-You are the fatamids (shia) trying to declare holy war on the seljuks (sunni) during their war with the byzantines, it isn't going to work.
-You are the fatamids (shia) trying to declare holy war on the seljuks after their war with the byzantines, it is going to work.
-You are a greek orthodox duke trying to declare holy war on a kurdish (sunni duke) in your new realm of the seljuk sultanate(sunni). It isn't going to work.
-You are a greek orthodox duke trying to declare holy war on a kurdish sunni duke who is not in your new realm of the seljuk sultanate. It isn't going to work.
-You are a greek orthadox duke trying to declare holy war on the fatamids (shia) while you're in your new realm of the seljuk sultanate. It is going to work. That said expect to lose the game very quickly.
-You are a greek orthadox duke trying to declare war on the mongols (pagan) while you're in your new realm of the seljuk sultnate. It is going to work.
-In the middle of this war they convert to sunni islam (the exact same as your liege), the war gets cancelled/white peaced at that moment (I think the game assumes a white peace, but I'm not sure).
-You are a greek orthadox duke trying to declare holy war on a greek bogomolist duke in your new realm of the seljuk sultanate. While it isn't the wisest move around it is going to work.
[/EDIT]
Relevent file: Crusader Kings II\Common\00_cb_types.txt
Search for "name = CB_NAME_RELIGIOUS"
Code:
name = CB_NAME_RELIGIOUS
can_use = {
ROOT = {
NOT = { religion_group = pagan_group }
NOT = { same_realm = FROM }
OR = {
NOT = { religion_group = FROM }
is_heresy_of = FROM
is_parent_religion = FROM
AND = {
religion_group = muslim
NOT = { religion = FROM }
FROM = {
NOT = {
any_current_enemy = {
NOT = {
religion_group = muslim
}
}
}
}
}
}
top_liege = {
religion_group = ROOT
NOT = { religion = FROM }
OR = {
religion = ROOT
AND = {
is_heretic = no
ROOT = { is_heretic = no }
}
}
}
}
}