Europa Universalis IV Developer diary 8 - With God on Your Side?

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Studio Manager Paradox Tinto
Paradox Staff
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Dec 14, 1999
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Welcome to a new developer diary for Europa Universalis IV and this week we say our prayers and address the often touchy subject of religions!
Religion has always been an important part of the Europa Universalis series and we've never shied away from modeling it, as delicate as it can be sometimes.
But face it – you can't have a truly deep game about this time period that doesn't try to treat religion with the importance it had over the time span of Europa Universalis IV.

This is the era when the Catholic Church sponsored great works of art while forcibly converting any non-Christians in Iberia. This game will see that same church splinter as corruption and argument over the power of the church gives rise to new interpretations of the word of Christ. The Orthodox Church helps engineer the rise of stable dynasty in Russia, and India sees one of the world's oldest faiths try to co-exist with the Muslim rulers that claim her. Not to mention the force of religion in the campaigns of exploration and conquest.
But in Europa Universalis, history is not destiny, so the religion you choose to follow is vital both in the relations to other countries and to your people.

Each religion matters
The religion that your country follows and how tolerant it is of other faiths is of paramount importance. Your religions will have an effect your diplomatic actions and countries of mutually accepted religions will have a better chance of reaching agreements with each other. Tolerance is also connected to the risk of revolt inside your empire. Provinces of untolerated religions are more likely to revolt against you; they do not share your faith, and so have no religious obligation to obey, and are likely to be dissatisfied with your religious decisions. As the empire builder, you have some control over things by having the option to change your state religion. You need to make religious decisions that may impact your internal and external religious relations, and, of course, you can send missionaries to convert infidel or heretic provinces to your country’s state religion.

Changed Effects of every religion
For Europa Universalis IV, we have changed the effects of every religion. Some religions will keep their traditional bonuses, like morale boost for Shiite Islam and trade boosts for Reformed Christianity. But a lot of new effects have been introduced, as well. For example, both Sunni and Shiite Islam have a larger chance of producing an heir, and therefore maintaining their legitimacy. One big change from earlier games in the series is no religion will give you a free colonist bonus, as was the case for Protestantism in previous titles.

Unique Abilities to Religions
The guiding idea is to make each religions feel unique to play. Except for matters of colonization, conversion or risk of schism, there wasn't much about religious matters in Europa Universalis III that you could point to and say “This is what an Orthodox country looks like.” Let's start with the familiar starting European faiths, since those are the ones that most people end up playing with. We have focused on developing three unique mechanics for Catholic, Orthodox and the Muslim religions.

Roman Catholics have a special challenge because they have the intricacies of the papacy to deal with. The Catholic hierarchy is led by the Pope and includes cardinals, and bishops. Europa Universalis III represented this with a curia - the system of reserved positions used to designate the administrative apparatus of the Roman Catholic Church, and more specifically, the Vatican. You could bribe the cardinals in the Curia to support your cause and if you took control of the Curia by having the most influence, then you would get a few bonuses here and there. The Papacy in Europa Universalis IV is rather different and, we think, improved.

First of all, the seven cardinals who make up the curia cannot be swayed. Still, the country with most cardinals in the curia is the Papal Controller. The person controlling the curia will gain a few bonuses including prestige and an additional diplomat. Given the scarcity of diplomatic envoys in Europa Universalis IV, this can be a hefty reward.

How do you get control of the curia if you can't bribe the holy men? There are now five cardinals on the outside, waiting to get in to the curia once another Cardinal dies. These cardinals can be swayed by investing your existing papal influence into them. So you are, in effect, spending assets on the chance that a cardinal you support will get promoted. Of course, you don't know how much others have invested in that cardinal so you could be wasting influence, and he may not live long enough to enter the curia anyway. But we hope that the prestige and diplomatic bonus make the curia a prize you cannot entirely neglect.

The Orthodox Church Established the seats of patriarchy where the patriarch is representing the community identified with his religious confession within a state or empire. The Orthodox Church has no similar supreme clerical infrastructure, but, historically, the active engagement of patriarchs like Nikon and Theophan could be a great asset to the royal agenda. So for the Orthodox religion, we have introduced the concept of Patriarch Authority, ranging from 0 to 100%. Since you are the monarch, you don't have a lot of direct control over the Patriarch's Authority, but choices you make throughout your nation's history will either give more power to the patriarch or take power away.
A high Patriarch Authority will mean extra manpower for your country as priests shame the peasantry into enlisting in your armies, and will also keep your revolt risk low. It might, however, also reduce your taxes as the church claims more for itself.

Sunni & Shiitie
Where the Orthodox are about Authority, the Sunni and Shia of the Muslim religions have the concept of piety.
Being Pious gives your troops improved morale, higher defensive power when under attack and lower revolt risk in those provinces that share your state religion. But piety can be a barrier to progress! A lack of Piety gives Islamic state more taxes & manpower, as well as cheaper technologies. Don't see Piety here as the difference between good and evil, but the difference between enthusiastic devotion to the idea that the state represents the community of faith and the idea that a nation might have interests distinct from those of Allah.
Piety is graded on a scale between +100 and -100, where being in the middle is sort of a gray state with no real bonuses at all., The real benefits on the Piety scale are on the extreme ends. When a new ruler succeeds to the throne, the Piety score is reset so you lost ¾ of your piety extremes, tending towards the middle. The new sultan is not assumed to be as impious or as pious as his predecessor. Unlike the Orthodox Authority, you have some control over how much Piety you have.. While there are events that affect your piety, your behavior it is the primary factor here. For example, declaring war on heretics and heathens increases piety, while declaring war on co-religionists decreases it.

Religious Unity
In the previous incarnation of the Europa Universalis series, having different religions in various provinces in your empire had a number of effects, some visible but some hidden in the math underneath the game. Along with changing the stability system, we are able to take one of the previously hidden effects and make it apparent to everyone – Religious Unity. Religious Unity is the percentage of your tax base that follows your state religion. So those few really wealth heretic provinces aren't the minor annoyances that they used to be, since their wealth and prominence makes their refusal to toe the line on matters of faith more than just a local issue. Religious unity directly affects revolt risk and stability cost, and Catholic nations get a benefit to Papal Influence if they have high Religious Unity.

The new Religion Interface

Here is a quick look at the new religion interface in Europa Universalis IV, from where you can easily manage all the relevant religious matters at once, including sending missionaries to heretic or heathen provinces.


That´s all for now, but you can rest assure that I´ll be back next week! Then I will take the opportunity to look into trade...
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Mmmmh. Seems good, yes. I want to see how being Innovative effects Religious Unity, since in EU3 the choice was to convert everything (as Innovative gave no bona whatsoever to tolerance and similar). Good job.;)
I see that Defender of the Faith will be included, but I wonder if it will have the same function. Hope that the Pentarchy event remains in the game. I love what you are doing with the Orthodox and Muslim faiths. Great work, can't wait.
I'm optimistic about these new mechanics, although as with everything I guess we'll have to wait until release to really find out.

What's the deal with 'tolerated' religions? How does that work, and can they change?

EDIT: Third! Wow, I sort of expected something like twenty people to post by the time I finished writing. :p
Don't really see the advantage of the old Curia system over the new one. The old one used papal influence + randomness to determine the cardinals and thus the Curia controller while the new one keeps both elements and adds a bit of clicking around to it?

But what's really important to me is how eastern religions are portrayed... those were lacking A BIT in EU3.
This sounds really good and alot more fluid than religion in EU3.... I like the double-faced approach to religion where you can either tie your country's goals with those of God or to distinct it and favour your own country's interests.... I hope this will allow more fluidity in relations between countries who have different religions.
Great DD! Thanks a lot! :) A few questions if you don't mind:

1) Is Sikhism going to make it into the game this time? I always thought India would be more interesting if it had its own "protestant" experience where a new religion would appear, provinces start converting via event, and you have to deal with it.

2) How about other eastern religions? Will they be getting any attention at all? I think Confucianism literally only had two decisions in EU3 and you could only take one of them. I know the game is EUROPA Universalis IV, but it would be nice if every religion has a handful of decisions. Give the player playing these countries goals to work toward.

3) How does religious conversion work? If I'm a pagan, can I just convert to Islam or Orthodoxy on a whim, or is it more like EU3 where conversion only happens through specific events/decisions and some countries will never have the opportunity to convert?
Will other religions than those presented get worked on to some degree? What I mean to say is, does Hinduism for example have any special mechanics?
First of all I'd like to state my enthusiasm, as each Dev Diary increases greatly my interest in EU IV, since it seems like most of my issues with EU III are being dealt away with one at a time! Good job Paradox!

I do think however that the way you seem to plan to handle Islam might be a wee bit off. First of all is the effect of Piety on technology - while this would work great for government techs and other social advancement inhibition, since there is the tendency to look back at the times of the Prophet as a model for the perfect state and society, the advancement of other techs should not be impeded by Piety, since there was very little opposition to what would be commonly referred to as technological advancement in that period - quite the opposite, the oldest Islamic universities were founded before the game's timeframe, and many innovations were introduced from the East through the eager adaptation of them by the Muslims - the Prophet Himself ordered his followers to "seek out wisdom, even as far as China".

The second thing I worry about is the question of taxes and Piety compared to Religious Unity. While it is obvoius that with an increased Piety the tax burden on the believers should be relieved, and thus less income from state-religion provinces, but it could potentially increase the tax (while reducing growth) of People of the Book (Christianity, Judaism) provinces. The fact was, that for many rulers of the time conversion of minorities was a financial drawback, while for many merchants the decision to convert was motivated economicaly. So while having less Unity might impede your Piety, a high Piety Ruler could benefit strongly from taxes on minorities, while a low Piety one could be seen as giving the minorities tax breaks but allowing merchants and artisians to prosper (increased growth and trade income from those provinces).

Just my two dinars ;-)
Seems like many good changes, though I find one of the changes for Islam is a bit lacking. Sure, there shouldn't be a big problem for a muslim ruler to have a heir, but historically there were often many who claimed to be heirs, thereby creating civil wars over who should rule after the monarchs death. So having a bonus in legitimacy isn't really the right way to go in my opinion, maybe a higher risk of pretender rebels would be more suitable.
NIce DD with many great changes. There's still lots of things that are not explained in this DD however, such as the more about the tolerance mechanics, the defender of the faith system, and conversion. Or do those basically stay the same compared to EUIII?
Seems like many good changes, though I find one of the changes for Islam is a bit lacking. Sure, there shouldn't be a big problem for a muslim ruler to have a heir, but historically there were often many who claimed to be heirs, thereby creating civil wars over who should rule after the monarchs death. So having a bonus in legitimacy isn't really the right way to go in my opinion, maybe a higher risk of pretender rebels would be more suitable.

Perhaps the way to go is to give an increased chance to produce an heir but at the same time add in a penalty to the heir's legitimacy. In EU3, when your heir had low legitimacy, there was an increased chance that pretender rebels would spawn on succession.
very very similar to eu3

Thanks for the quick reply. Cant say i wasnt hoping you say something about it being complicated and dynamic though, but as with EU3 mods'll step up to that so no worries.
DDs have all been looking great so far, stellar work.