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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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I see the reasoning behind holy wars costing you fervour. But on the other hand... yeah, we are talking about a time period where winning wars and battles was largely seen as a sign of divine approval. Plus I do not think there were many new heresies created because Charlemagne conquered some Germanic pagans, rather the opposite. It seemed to strengthen Western Christianity.
 
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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?
Probably nowhere, it doesn't matter, it's a gameplay solution to stop powerful religions from snowballing weak religions and ensure that there can be an interesting religious situation on the map even later on in the campaign, such as powerful religions suffering temporary bursts of heresy or weak religions being able to rally against their encroaching enemies.

If you're desperate for a flavour explanation then assume that rallying people for holy wars "spends" their religious fervor. You don't lose fervor for winning but just for declaring channels popular religious zeal making them less interested in joining for the next ones.
 
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it's a gameplay solution to stop powerful religions from snowballing weak religions
But, I mean--shouldn't they?

I don't mean that an intolerant sort of way. But there's a historical reason why Zunism didn't survive and Abrahamic religions won in the region depicted here (minus India), particularly that they are good at converting, fond of holy wars no matter the cause, and simply have more adherents to begin with. The fact that a player can turn that around and make a pagan faith dominant means that they're a good player and present an interesting what-if scenario, sure, but as the EU dev diary today points out, the AI forming a majority non-Abrahamic Europe quickly is unrealistic.
 
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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
Not really: "Hostile" is the threshold for holy wars and nobody would ever think of having a holy war between Insulars and Catholics at the time. The churches in Ireland were still considered and also considered themselves to be in communion with Rome, even if there were tensions about local rites and practices being non-standard compared to Rome.
 
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You need to use either a Tenet or a Doctrine to change religious hostility. Either option works just as well; Ecumenism is a Doctrine for example, while Christian Syncretism is a Tenet.

Currently only Gnostics are able to achieve a Righteous view of other Faiths, but mods can change or expand upon this to enable schism reformations and the like without too much trouble.

I encourage you to look for a way to represent the Schism, so that, in the early years, Catholics and Orthodox view each other as Righteous.
 
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I died a little inside when I saw the Lollards are making a comeback. Unless you're planning to stretch the game through to the 16th century these guys really shouldn't be making an appearance. No doubt we'll be seeing a return of late 15th century Muslim heretics the Zikri too.
 
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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.
Question, how well will the system deal with religious fervor locally? IMO the system should not be pure global based. News dont travel that efficient in those days and I'd imagine your local hedonist cannibal duke, local bishop should have the same weightage as corrupt pope across half the continent; then a random petty king that not everyone cares about, locally should have far less effect on that person's religious fervor...
 
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If Catholic has the "ecumenic" trait, then an heresy having the ecumenic trait will be considered "just" astray?

Which make perfect sense, especially if we consider Ireland, which should be also be ecumenical but a different Christian faith then Catholic, as they didn't answer to the pope until the 12th century and their church leadership was based around monasteries instead of bishopric.
 
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I encourage you to look for a way to represent the Schism, so that, in the early years, Catholics and Orthodox view each other as Righteous.

I would argue that they saw each other, de facto as astray, as represented here. Before the Schism, due to centuries of differentiation in religious practice and after the Schism as well (the so-called 'Great Schism' was not seen as important by any people at the time.)
 
But, I mean--shouldn't they?
No.

If you want interesting and dynamic religious gameplay in this game you probably don't want for Catholicism, Orthodoxy, Sunni denomination #3 and Hinduism to be the only surviving religions 100 years into the game and then never ever change whatsoever due to how powerful they are. You want a system where even strong religions can suddenly struggle with heresies (like it historically happened with Catholicism in Europe, as the latter part of the Middle Ages was all about the Papacy struggling with antipopes and heresies popping out in protest to the perceived immorality of the clergy) and weak religions aren't doomed to disappear in a death spiral caused by military losses to stronger opponents.

I don't mean that an intolerant sort of way. But there's a historical reason why Zunism didn't survive and Abrahamic religions won in the region depicted here (minus India), particularly that they are good at converting, fond of holy wars no matter the cause, and simply have more adherents to begin with. The fact that a player can turn that around and make a pagan faith dominant means that they're a good player and present an interesting what-if scenario, sure, but as the EU dev diary today points out, the AI forming a majority non-Abrahamic Europe quickly is unrealistic.
Why are you even bringing up non-Abrahamics? The system is just meant to make it possible for Cathars to pop up in Europe and be an issue like they historically were even if Catholicism is militarily strong. I have absolutely no idea where you got the idea of Europe being converted to paganism quickly from.
 
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Will there be any religious dynamic events? The thing about CK 2 is that it felt the same no matter how many years the game went on. CK 3 has addressed many of the more dynamic upcoming aspects about the game, but what about dynamic events? I'm going to illustrate what I mean. But in short, they are pretty similar to the Crusades, which is a perfect example of a dynamic event where the game adapts to recent changes.

The examples below will be based on Catholicism and should be tweaked to fit the other religions as well. These ideas are thought up in the concept of CK 2, so I do not know whether or not all of them can be implemented in CK 3. But I will list the examples anyway, as I think dynamic events like this may add a lot of flavor to the game.

1. Religious Orthodoxy as a response to a longer period of high moral authority
The catholic faith has reached its maximum moral authority and there is no doubt in the legitimacy of its dogmas and religious institutions be it from the peasants or from the nobility. During this period, the religious zeal is at its peak. Virtues are considered even more valuable than before, granting an increased opinion among the clergy and a bonus to overall stats, and it's more important for a ruler to be pietous than to be prestigious. Sinful rulers are pennalized and the Holy Orders gain a +30% morale damage and defense buff. The Pope is likely to grant others claims for titles if he considers the ruling dynasty or men unfit for their position.

2. Prestige and hedonism as a response to a low moral authority and and abnormal amount of epidemics and warfare
In the last decade, the world has seen an abnormal amount of epidemics and warfare, resulting in the peoples' questioning of the Lord almighty. Noble rulers have taken the opportunity to exalt worldly features. The worth of Prestige has been doubled and characteristics associated with vices have changed for the better, all while the worth of Piety on the other hand has been halved and rulers favoring virtuous traits are now seen as weak and meek. Noble adventures are more likely to appear in conquest for their claims.

3. Witch Hunt as a response to apostasy and witchcraft
It has come to the clergy's attention that more and more people have turned away from the gospel to embrace the sweet promises of the dark lord. All around the Christian world, the clergy are encouraging the hunting of witches and apostates. Rulers are expected to hunt witches, and they are expected to burn anyone accused of witchcraft, no matter be it a close relative or a lowborn stranger. Rulers who let an accused witch go free, may get excommunicated and accused of apostasy him- or herself. On the other hand: those who make a name for themselves as an outstanding beacon of faith, may leave a bloodline behind.

4. Religious revolt as a response to religious oppression
Infidel rulers have settled down on Christian land, seeking to proselytize their Devilish Religion. In this dark times, the Catholic Pope of Rome is especially looking at the Visigoths suffering under Umayyad rule in Iberia. In a major speech, The Pope urges the people of the land to take up arms [Catholic uprising revolts], knowing that the Pope - and God - stands with them! Catholic Peasant revolts in infidel lands have now increased to a global +10% for one year. Religious revolt risk has been increased among Catholic peasantry in all counties ruled by secular rulers not of the catholic faith. OBS: I know that CK 3 has a different revolt system, so changes can me made to increase instability in counties.

5. Bonus moral authority events for heretics as a result of heretical expansion
For some time now, heretics have gained political influence, winning terrain. The Catholic Pope seems unable to hold the Christian realm together, making some question if he truly has the blessing of the Lord almighty. Catholic moral authority will now be lowered by -10 for the next 10 years while all Catholic heresies will get a +10 buff each.

6. Free investiture events as a result of failed crusades and low moral authority
The Noble leaders have for a long time been dissatisfied with the ruling Pope of Rome. Failed Catholic Crusades and his inability to combat heretics have resulted in the cynical, cruel, arbitrary, ambitious or envious leaders, or those excommunicated and or with a negative opinion of the pope, to implement Free Investiture [automatic change]. The Pope is not pleased. OBS: CK 3 will have a different trait-system than in CK 2, so the listed traits can be replaced with what is suitable for CK 3.

7. Continuation of the Free Investiture event above (#6)
To combat the nobles' grasp on the spiritual power, the Pope of Rome has started a decree where he threatens to excommunicate all leaders with Free Investiture unless they change their laws in accordance with the will of the Church. Each ruler with Free Investiture have now been given an option to decide [automatic change].

8. A religious (last) stand as a result of low moral authority and low religious population
To counter the decreased Moral Authority of the Catholic Church, the Pope of Rome has started a campaign where he urges all true believers to take up the spiritual fight against evil. Catholics will now be harder to convert, some might gain the Zealous trait and those secretly Catholic will openly practice their beliefs!

9. Religious anti-papal war as a result of the current Pope being a wicked priest
For some time now, the Pope of Rome has reigned over the Spiritual world in sin. An immoral man of the cloth, the pious rulers of the Catholic world no longer recognize his claim. An [independent] Antipope has been setup [random among the Cardinals?] and all rulers have been given an option to determine whom to recognize as the true successor of Saint Peter. Furthermore, they have started a war to depose of the old Pope! Trembling in fear, the Pope of Rome asks all true pious Catholic rulers to take up arms in defense of the lord almighty! All true pious Catholics willing to lend him a hand will be greatly rewarded should he win! (Piety, Paragon of virtue? Coronation / Sainthood?).

These are some examples, hope you found them to your liking! Note that the idea of the events above is what I'm trying to point out, and not the specific examples. Examples may be added or removed but the point of dynamic events is what's of importance and which may be a very good asset to the game.
 
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The Roman Sun worship, that of Sol Invictus, had its major celebration on 25th December, not in the summer, as can be seen in this Roman calendar.
Now that sounds familiar somehow ...

No.

If you want interesting and dynamic religious gameplay in this game you probably don't want for Catholicism, Orthodoxy, Sunni denomination #3 and Hinduism to be the only surviving religions 100 years into the game and then never ever change whatsoever due to how powerful they are. You want a system where even strong religions can suddenly struggle with heresies (like it historically happened with Catholicism in Europe, as the latter part of the Middle Ages was all about the Papacy struggling with antipopes and heresies popping out in protest to the perceived immorality of the clergy) and weak religions aren't doomed to disappear in a death spiral caused by military losses to stronger opponents.


Why are you even bringing up non-Abrahamics? The system is just meant to make it possible for Cathars to pop up in Europe and be an issue like they historically were even if Catholicism is militarily strong. I have absolutely no idea where you got the idea of Europe being converted to paganism quickly from.

I propose events that erode the Fervor of faiths whose clergy are rich - that way, we can let holy war successes translate into Fervor hits down the line instead of immediately.
 
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Can different faiths have the same religious head? for example, can Maronites recognise the Pope but follow their own rites? Do the Celtic Christians acknowledge the Pope as the head of their faith but still marry?
 
But, I mean--shouldn't they?

I don't mean that an intolerant sort of way. But there's a historical reason why Zunism didn't survive and Abrahamic religions won in the region depicted here (minus India), particularly that they are good at converting, fond of holy wars no matter the cause, and simply have more adherents to begin with. The fact that a player can turn that around and make a pagan faith dominant means that they're a good player and present an interesting what-if scenario, sure, but as the EU dev diary today points out, the AI forming a majority non-Abrahamic Europe quickly is unrealistic.
No. It often took centuries to completely wipe out a religion. I mean, Zoroastrianism still survives to this day. It makes a lot of sense that as religions become more persecuted and diminished to smaller but more concentrated communities, the zeal in those communities toward maintaining their traditional beliefs against the push of conversion efforts would be extremely strong.
 
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and weak religions are doomed to disappear in a death spiral caused by military losses to stronger opponents
The heretical faiths may appear, but will be quickly suppressed, which is, yes, realistic. Cathar endurance and victories were due as much to the sociopolitical factors of the time unrelated directly to religion as to the direct brutality of the Church-sponsored forces.

Why are you even bringing up non-Abrahamics? The system is just meant to make it possible for Cathars to pop up in Europe and be an issue like they historically were even if Catholicism is militarily strong. I have absolutely no idea where you got the idea of Europe being converted to paganism quickly from.
Well, because if you don't have a heretic outpost on your borders, what's going to be the next "weak religion" to be targeted by a Holy War CB? The way OP phrased it there suggested it was intended to gameplay balance all Religions as well as Faiths (remember, in CK3 terms Cathars are of course still Christian, just a separate Fatih).
 
My questions:

  1. What family does Zoroastrianism belong to?
  2. Will Tengrii have a special tenet allowing them to Marry "evil" faiths?
  3. Is the marriage restriction just for the offer recipient?
  4. Will Jainism be the most stubbornly persistent religion under this system?
  5. Can heresiarchs espouse a new faith belonging to a different religious family? E.g. a pagan revival in Christian Europe, a Tengrii spontaneously converting to Judaism, or an Indian Hindu adopting an obscure branch of Christianity.
  6. Are there any tenets that increase hostility? There were many minor "heretical" Eastern religious leaders who advocated religious violence and intolerance.
 
The heretical faiths may appear, but will be quickly suppressed, which is, yes, realistic. Cathar endurance and victories were due as much to the sociopolitical factors of the time unrelated directly to religion as to the direct brutality of the Church-sponsored forces.
The Cathars weren't unique in their strength or how long they lasted though. For one, the Waldensians lasted for centuries in Swtzerland, Italy, and France even influencing Reformation thinkers and, by the way, they're still around today. The idea that the Cathars were unique as a Catholic heresy that wasn't quickly suppressed is really wrong.
 
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