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Dev Diary #24 - Fervor, Religious Hostility, and Doctrine Showcase

Hello everyone, and welcome back to our final Dev Diary on Religion in Crusader Kings 3! Today I will be talking about what the mysterious Fervor is, how that ties into Heresies and Heresy Outbreaks, as well as how Religious Hostility works and some of the ways that Doctrines can impact it. To wrap things up, I will show off some additional never-before seen Tenets and Doctrines!

Fervor
Every Faith has a Fervor score, which is a representation of how strongly adherents of that Faith believe in the righteousness of their religious and secular leaders. While Fervor has a slow ticking increase over time, it is primarily influenced by the virtuousness or sinfulness of that Faith’s leaders. Virtuous priests can inspire a populace and rally the people behind themselves, while sinful ones (especially religious heads) can cause massive scandals that damage the faithful’s trust in their religious institutions.

DD_WM_Scandal.png

[A screenshot of the Pope looking very guilty after being caught in flagrante]

Adherents of a Faith with high Fervor are willing to fight and die for their beliefs. They gain bonus resistance to attempts to convert them to another faith, and both secular and religious leaders can declare Holy Wars to spread their Faith across the world. However, while these Holy Wars are ostensibly waged in the name of the divine, in practice they often tend to be little more than opportunistic land-grabs — as a result, every Holy War declared will slightly damage a Faiths’ Fervor, while losing land to hostile Holy Wars will actually increase your Faith’s Fervor as the embattled faithful dig in and fight for their way of life!

When a Faith’s Fervor drops, adherents of that Faith become vulnerable to conversion. Characters are more willing to accept a Demand Conversion when their Faith’s Fervor is low, and the Court Chaplain’s ‘Convert County’ task gains a scaling bonus against Faiths whose Fervor is lower than their own. In addition, if Fervor drops low enough, a Faith becomes vulnerable to heresy outbreaks!

Heresy Outbreaks
A heresy outbreak is what happens when a ruler becomes disillusioned with their current Faith and is swayed to join a different one. If there is already a heretical Faith present nearby, they will convert to that one automatically. If no suitable heresies are around, they will become a heresiarch and start espousing the doctrines of a brand new Faith, which is typically (but not always), one from their Religion.

A ruler who converts to or founds a new heretical Faith will then attempt to convince nearby rulers of their old Faith to join them, with the success rate of this being dependent on how low their old Faith’s fervor has fallen. This means that while heresy outbreaks can vary wildly in size, converts to the new heresy will tend to remain clustered together in a specific region — this both protects the burgeoning Faith while simultaneously limiting its influence in distant lands.

DD_WM_Heresy.png

[A screenshot showing an outbreak of Lollardy, originating in southern England]

As you can imagine, heresy outbreaks are incredibly divisive events; nobody wants to sit on the fence when your immortal soul is on the line! As a result, after a heresy outbreak occurs both the old Faith and the new heretical Faith will gain a substantial increase to their Fervor score. As this is likely to encourage Holy Wars for both sides, it is not uncommon for a new period of religious violence to follow as the two Faiths fight for supremacy!

Ultimately, the flow from scandal to heresy to zealousness and back will cause Fervor to vary wildly over the course of a game of CK3. Unlike the relatively static Mortal Authority in CK2, this means that even the big dominant religions will have periods of weakness, making them vulnerable to fractures and religious violence.

Religious Hostility
Speaking of religious violence, how does that work? With so many different Faiths and Religions in Crusader Kings III, how do they view each other? What is the difference between how an Orthodox ruler views a Catholic, a Bogomil, and an Ash’ari?

In Crusader Kings III this is all handled by the Religious Hostility system. For characters of a given Faith, every other Faith in the game will receive one of the following rankings:
  1. Righteous
  2. Astray
  3. Hostile
  4. Evil
Righteous is how a Faith views itself and, in a few rare circumstances, other Faiths that have certain things in common with it. Righteous Faiths have no penalties at all with each other.

Astray is how a Faith views other Faiths that have similar goals and ideals but are just a little… wrong. For example, Orthodoxy and Catholicism consider each other to be Astray. Astray Faiths have only a minor opinion penalty with each other.

Hostile is how most Faiths view their heresies and other significantly divergent Faiths. Opinion penalties are more substantial at this level, and rulers gain the ability to declare Holy Wars against rulers of Hostile Faiths. However, intermarriage is still common when it is politically convenient, and alliances can still be forged between rulers of Hostile Faiths.

Evil Faiths are considered to be an anathema, and cannot be tolerated. Evil Faiths suffer the most severe opinion penalty possible, and Holy Wars against each other become commonplace. Rulers will almost never accept marriages with characters of an Evil Faith, making alliances all-but-impossible.

So how is Religious Hostility determined? The primary factor is what Religion Family both Faiths belong to:

DD_Hostility.png

[A screenshot of a spreadsheet showing how base Religious Hostility is calculated, with Abrahamic Faiths being the least tolerant and Eastern Faiths being the most tolerant]

But wait, if Abrahamic Faiths view other Faiths within the same Religion has Hostile, why do Catholicism and Orthodoxy only see each other as Astray? The answer to that, my friend, is Doctrines!

Doctrine & Tenet Showcase
Now we’re going to take some time to reveal a bunch of the various Doctrines and Tenets available for Faiths in Crusader Kings 3. For starters, the Catholic, Orthodox, Apostolic, and Coptic Faiths all have the ‘Ecumenism’ Doctrine, which changes the Hostility of any other Faith with the same Doctrine to just ‘Astray’, thus allowing these Faiths to have cordial relations with each other.

DD_WM_Doctrine_Ecumenism.png

[A screenshot showing the Ecumenism doctrine, which reduces Hostility between certain Christian Faiths]

In a similar vein, the various Muslim Faiths all have a doctrine representing their belief in the true succession for Muhammad. The various Sunni Faiths all see each other as Astray, with the same being true for the collective Shia Faiths and the collective Muhakkima Faiths.

The embattled minority of Gnostic Faiths have an ever stronger version of this; having always struggled to have their beliefs accepted, they see all other Gnostic Faiths as being fully ‘Righteous’. This allows us to have coalitions of Faiths within or even outside of a Religion that see some Faiths as allies and others as enemies, completely changing the dynamic of how religious relations play out in Crusader Kings III.

DD_WM_Doctrine_Gnositism.png

[A screenshot showing the Gnosticism Tenet, which among other things eliminates Religious Hostility between Gnostic Faiths]

Finally there are other Tenets which can modify how your Faith sees, and is seen by, Faiths in other Religions.

DD_WM_Doctrine_Syncretism.png

[A screenshot showing various Syncretism Tenets, which reduce Religious Hostility across entire Religions]

Diplomacy not your thing? Try some warfare!

DD_WM_Tenets_Warfare.png

[A screenshot showing various warfare-focuses Doctrines and Tenets, including Armed Pilgrimages which enables Crusades]

Or is all of this just too secular for you? After all, isn’t religion supposed to be about spiritualism, a belief in otherworldly entities beyond our understanding? Well then maybe one of these tenets would suit you...

DD_WM_Tenets_Mysticism.png

[A screenshot showing various Tenets of a more spiritual nature: Astrology, Auspicious Birthright, Reincarnation, Sun Worship, Sky Burials, and Esotericism]

Of course, this is just a sample of the Tenets and Doctrines that we have in Crusader Kings 3. It would take too long to go into this level of detail for all of them, but here is a teaser of some available Tenets on the Faith Creation screen, showing both some previously revealed and unrevealed Tenets.

DD_WM_Tenets_List.png

[A snippet of a handful of available Tenets from the Faith Creation screen]

That’s all for now — hopefully this post has given you something to think about as you plan your first campaign of Crusader Kings III, and every one after that!
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical
 
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@Baron von Shoes

A couple of further questions:

1. Are there going to be fantasy elements like in the latest editions of CK2? By that I mean e.g. the following question: will Astrology's "Divine the Stars" just give some sort of a morale boost (or stuff like that), or will the mechanics assume that "predicting the future" can actually work? Same question regarding "Miracle Workers" (will the mechanics assume that "miracles" can actually happen?) and so on.

2. Why is Sky Burial giving a health boost? I'd say that it should rather give a malus to health, due to birds spreading diseases from corpses.
 
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I am uncertain why Abrahamics see each others faith as evil instead of hostile. I don't think that, say, Catholics saw Sunni or pagans as fundamentally more evil than Cathars.
I think that "evil" conveys something akin to satanic cannibalistic cult, not established religion that countries that practice it maintain diplomatic relations with. I'd limit "evil" to religions that have at least one total opposite tenet or doctrine, such as all religions that see honest as virtue will see those with sacred lies tenet as evil instead of merely hostile, or those who allow witchcraft vs those who criminalize it.

And all gnostics seeing each other as righteous is a bit too generous in my opinion, it's not like various sects didn't bicker with each other when they had the opportunity, it's just that most of time they were too busy with being stomped on by mainstream religion.
 
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As a mechanic, this is fine; it'll keep realms from exploiting Holy Wars for blobbing.
As a representation of RL, I think it misses the mark: I'd imagine people's fervor would spike after a calling for an Holy War that would retrieve land and righteous believers from heathens. And even more if it's successful.

When can we see the new units in detail, and is there going to be different types for the different culture groups?
I think you have it backwards. You need to whip people up into a religious fervor to get them motivated enough to declare the Holy War, otherwise most people are just going to shrug and question why they're being asked to fight a war thousands of miles away. For the purpose of declaring holy wars, fervor is more like political capital.
 
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@Baron von Shoes

There were many medieval periods when Abrahamic religions managed to coexist peacefully with other religious groups, and ally and even intermarry each other.
- Islam obviously included a lot of Christans, Jews, and later Hindus on its realms and it varied greatly between periods of religious persecution and relatively high tolerance
- There was a famous case of multicultural Sicily
- Christian and Muslim realms in Iberia did frequently ally "infidels" to fight "brethren"
- Georgians and Armenians largely coexisted with Muslims (well how would they survive otherwise)
- Even in India Muslim invaders had periods of high tolerance for Hindus (it was way worse for Buddhists)
- Crusader states also wouldn't survive as long if they didn't practice reasonable diplomacy with Muslims neighbors

So, how is all of this modeled in game?
 
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Fervor is global for the entire Faith. However, the more dynamic nature of the Fervor system means that Faiths simply won't end up in the 'heresy death-spiral' that CK2 had, since Fervor will jump back up after an outbreak and give the original Faith some breathing room to recover and deal with the heretics.
No more heresy death spiral is the best feature of CK3 so far.
 
No more heresy death spiral is the best feature of CK3 so far.
Now I'm wondering what the best way to spread a new faith is. I guess successive rounds of conquest and conversion and stabilization.
 
I am uncertain why Abrahamics see each others faith as evil instead of hostile. I don't think that, say, Catholics saw Sunni or pagans as fundamentally more evil than Cathars.
I think that "evil" conveys something akin to satanic cannibalistic cult, not established religion that countries that practice it maintain diplomatic relations with. I'd limit "evil" to religions that have at least one total opposite tenet or doctrine, such as all religions that see honest as virtue will see those with sacred lies tenet as evil instead of merely hostile, or those who allow witchcraft vs those who criminalize it.

And all gnostics seeing each other as righteous is a bit too generous in mind opinion, it's not like various sects didn't bicker with each other when they had the opportunity, it's just that most of time they were too busy with being stomped on by mainstream religion.
I think the wording is just a bit off, where realistically evil would be on a level bellow its current position, however what is now "evil" should still have the same consequences as it has now. And since satanism isn't probably a thing in Ck3 having another layer might be a bit redundant.
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical
The loss of fervor probably represents people getting tired of fighting more and more holy wars, whereas people who are losing more and more territory want to fight back all the harder since they don't want to lose their land the same way others did.
In my honest opinion the system just needs to have a cap for how much fervor can be lost in this way (and possibly even gained).
 
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There were many medieval periods when Abrahamic religions managed to coexist peacefully with other religious groups, and ally and even intermarry each other.

Agree, I'd really like to see this sort of "localized syncreticism" that doesn't affect the entire faith, just a particular region with multiple faiths. May not be that relevant, though, since CK games generally don't represent multiculturalism/multi-religion regions very well (compare, like, how Stellaris handles pop species now: pie charts for everyone).
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical

The First Crusade focused on retaking land, recapturing Nicea which had been taken just a decade earlier, and other territories seen as "theirs". Then the fall of the crusader state of Edessa triggered the second Crusade. Then the fall of Jerusalem triggered the Third Crusade.

What it horrendously misrepresents is the Rise of Islam and fall of Zoroastrianism. But honestly, any system that could represent that period of history accurately would make for a terrible game, because Mohammed and the Rightly Guided Caliphs were crazy OP.

And Fervor isn't lost by winning wars. It's lost by declaring them, and only by a slight amount. So you can't have everyone spamming it - and Oh, look, in real life there was a cooldown period between Crusades, and it wasn't just exactly 30 years but rather was related to events going on at the time.

C.f. say Bogomil and Bogomilism. It was founded in the 900's around the time Christian rulers were getting involved in tons of wars with pagans all over Europe, to mixed results, though rarely outright losing territory to Pagans.
 
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Just a small idea.

Give a small mitigation to opinion penalties between two Astray religious followers if there is a hostile religion bordering (or nearby) both rulers.

The 'we've got bigger problems than each other' consideration.

Same could be done for hostile Vs evil too.
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical

I think you have it backwards. You need to whip people up into a religious fervor to get them motivated enough to declare the Holy War, otherwise most people are just going to shrug and question why they're being asked to fight a war thousands of miles away. For the purpose of declaring holy wars, fervor is more like political capital.

Yeah, I think it makes sense this way: the first few holy wars, especially if they liberate a holy site, will still leave a faith with high enough fervor. But once the holy land is already in Christian hands and kings keep on invoking non-stop holy wars to justify land grabs in far-off places in Persia and the Arabian peninsula, fervor is going to take a hit because people can tell the religion is being used cynically and opportunistically.
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical
As far as losing making someone more fervent, the Crusades being won and lost had a tendency to make the loser more fervent with regard to re-capturing the lost Holy Land.

With winning reducing how fervent people are... perhaps the idea is to encourage them to consolidate the land they've taken, convert their new population and then push onwards.
There's also a need to work up a new wave of interest in another Great Holy War against a new target.
 
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People can "respectfully disagree" with my comment, but no one seems to have an actual argument that they're posting - when in real life did a religion winning wars against other faiths make its adherents less fervent in their faith, and when did losing make them more fervent?

How could you say the first crusade weakened Catholicism and made heresies more likely to pop up? How can you say that Zoroastrians being wiped out made them stronger when in fact their religion collapsed more than ever? It's a nonsensical mechanic. I get why it's implemented, you don't want snowballing and you want it to be harder to wipe out faiths like Catholicism or Sunni Islam, but please do it a different way and don't punish players for success, because that's just annoying and ahistorical
Most historical heresies, at least of the Christian variety, have been condemnations of how much wealth those higher up in a faith and its clergy have. So it makes sense that the more temporal power a faith (and especially the leaders of that faith) has, the greater perception among both secular leaders and the more spiritual minded clergy that the faith is corrupt and out of touch with the common people, and calls will be made for a rejection of that wealth and power with new teachings as a rejuvenation of the faith's guiding principles. Look at the origins of the Waldensians and Lollards.

Plus, the Second and Third Crusades were started by the loss of holy wars (the falls of Edessa and Jerusalem respectively).
 
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It looks great. I suppose a Christian tenet could be 'Communion with Rome' which destroys your Head of Faith (i.e. makes the Pope your HoF) but makes Catholicism and you consider eachother righteous, provided certain other triggers are in place (maybe at most 1 other tenet difference?). In that case it would also make things like the Council of Florence possible - an Orthodox ruler deciding to reform his faith to be friendlier with the Pope, but getting internal resistance to changing the faith.

And the fervor-for-Holy-War thing, while obviously a rubber band kind of mechanism and thus hard to truly justify (since game probably came before justification), does fit with how these things went; the French were much more militarily religious when they could hop over the Pyrenees to help the Spanish, and a lot more cynical when there were catholic all around them with little risk. And Catholicism's largest fervor after the Crusades was probably the Reformation era.

Loss leads to a desire to fight back; only long-term repeated loss leads to disheartening, which could be a separate mechanic (maybe just a result of having no Holy Sites).
 
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Yeah, I think it makes sense this way: the first few holy wars, especially if they liberate a holy site, will still leave a faith with high enough fervor. But once the holy land is already in Christian hands and kings keep on invoking non-stop holy wars to justify land grabs in far-off places in Persia and the Arabian peninsula, fervor is going to take a hit because people can tell the religion is being used cynically and opportunistically.
An idea: if a Faith's Holy Site belongs to the territory targeted by a Holy War, don't reduce the Fervor for declaring said Holy War (and maybe even increase it), but if the targeted territory contains no Holy Sites of this Faith, do apply the Fervor reduction.
 
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DD_Hostility.png


So, if you are Abrahamic (as Christians will be), and both same family/same religion (as different Christian faiths will be), you are looking at different faiths being "hostile" by default.

Same family/same religion implies "Different faith" here.

Yeah that makes sense to me, and "Hostile" fits with what happened to Insular Christianity irl: The lack of papal control over how things were run in Ireland is what led to the pope at the time (the only English pope) giving the English king the sanction to invade Ireland and reassert Roman authority and implement Roman reforms
 
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