- Catholicism: the Pope
- Orthodox Christianity: the Ecumenical Patriarch
- Miaphysite Christianity: the Coptic Pope
- Sunni Islam: the Sunni Caliph
- Shia Islam: the Shia Caliph
Unreformed Pagans have no religious head, although they can create one by reforming the religion, called the High Priest or (for Germanic) Fylkir. Some heresies also have heads, not all of which exist at game start but can be created by decision. Some religious head titles cannot be destroyed, but are always held by some character; for some heresies, frequently the only character of that religion is its head. Indian religions also have no religious head.
In most religions the religious head is part of the clergy. In Islam and reformed Germanic paganism he is a noble who often wields considerable secular power. Religious heads may grant divorces, call Crusades, jihads and great holy wars (except Orthodox and Miaphysite and their heresies), and sanction invasions. The Christian religious heads can also excommunicate members of their church.
There is also a separate but related concept of a character's religious head, which is not always the same as the religion's head. This is particularly important for Orthodox and Miaphysite Christianity, which have autocephalous patriarchs; they have limited power compared to other heads. It is also relevant for Catholicism when antipopes exist.
The Pope is the head of the Catholic Church, usually residing in Rome. His title has the rank of king, so he cannot be vassalised except by an emperor. The Sons of Abraham expansion added a number of unique features to the Papacy.
Main article: Papal succession
The Pope is elected by the College of Cardinals. In-game, there are nine cardinals at a time, and when the Pope dies, the cardinals elect one among their number to replace him. Vacant cardinal positions are awarded to bishops based on their total suitability score. This is calculated based on the age, traits, culture, and secular power (rank and number of titles held) of the candidate, as well as the Pope's opinion of the bishop's liege. Rulers may invest in a campaign fund to increase the chance that their candidate will be chosen.
The cardinals choose the next Pope based on a similar ranking system, which rulers cannot directly influence. However, Popes who received votes from cardinals from a particular ruler's realm will have a massive +100 relations modifier per vote received.
Catholic leaders in good standing with the Pope can call upon him for special favours. Most of these require the Sons of Abraham DLC; the exceptions are divorce, excommunication and invasion. You can ask the same things of an antipope. The piety cost is halved for realms under Papal Investiture law.
|Ask to nominate bishop||0||480 months||If under the Papal Investiture crown law|
|Ask for divorce||100 piety||-10||480 months||Spouse's family unhappy.|
|Ask for claim on duchy or county||100 piety||-15||480 months||By selecting "claim" when viewing the title screen for a duchy or county. This will only be granted if the Pope dislikes the current ruler of the title. Cannot be used for prince-bishoprics or republics.|
|Ask for excommunication||100 piety||-25||480 months||Pope must dislike ruler. The target must control fewer cardinals than you do and have the same religious head as you. Moral authority > 40%|
|Ask to lift excommunication||50 piety||-25||480 months|
|Ask for money||100 piety||-50||480 months||Gives double ruler's annual income. Antipopes and vassal popes generally won't have much money to give.|
|Ask for invasion||-100||480 months||Pope must dislike ruler. Invasion casus belli. Moral authority > 50%|
|Ask for crusade||-200||480 months||Moral authority > 5%|
Main article: Antipope
Antipopes are a special feature of Catholicism. They are bishops controlled by a ruler, and hold a rival claim to the papacy.
If the Sons of Abraham DLC is active and Rome is held by a Fraticelli ruler, that ruler can, by decision, create the Fraticelli Papacy for a cost of 1000 piety. The Fraticelli religion works just like Catholicism, except that the Fraticelli Pope is duke-tier instead of king-tier.
Main article: Autocephaly
Some religions have a feature called autocephaly with intermediate religious heads called Patriarchs, autonomous in their jurisdiction, but reporting to an overall head.
The following religions use autocephaly and have the associated overall religious head:
- Orthodox: The Ecumenical Patriarch (usually in Constantinople)
- Miaphysite: The Coptic Pope (usually in Alexandria)
- Monophysite: The Monophysite Pope (usually in Alexandria)
- Nestorian: The Patriarch of the East (usually in Antioch)
- Monothelite: The Monothelite Patriarch (usually in Antioch)
- Iconoclast: The Iconoclast Patriarch (in Constantinople, if formed)
- Paulican: The Paulican Patriarch (usually in Constantinople)
These always exist, except that no one holds the Iconoclast Patriarchate initially; if you have the Sons of Abraham DLC, the Iconoclast Patriarch can be created decision by the liege of the Bishop/Patriarch of Constantinople if both are Iconoclast.
The exception is in 769, where the nobles and Baselius of the Byzantine Empire are Iconoclast, where Constantinople (the bishopric) is held by the Iconoclast Patriarch. However, any Byzantine Emperor who is not Zealous can denounce Iconoclasty, converting him and the Patriarch to Orthodoxy (destroying the Iconoclast Patriarchy and granting him the Ecumenical Patriarchy in the process). Until this decision is taken, the Ecumenical Patriarchate does not exist.
The Ecumenical Patriarchate is king-tier, and is usually the Byzantine Emperor's vassal and religious head (so he cannot appoint an autocephalous patriarch, but he has all the benefits of one); the rest are duke-tier.
Bogomilism, though a heresy of Orthodoxy, has no head. The same applies to Messalianism.
The Patriarchate has a unique mechanic of usurping their capital barony. The only requirement for this is that the bishopric in question is held by a character of the same religion as their head.
Upon doing so:
- they will receive the barony in question
- if the barony was the capital of a county, they will obtain the county title and all other baronies associated with it
- will become the vassal of the lowest-ranked ruler that can vassalize them
An example of the above: The Bishopric of Alexandria is currently held by a Miaphysite character. His lieges are, in order, the Count of Alexandria, the Duke of Alexandria, the King of Egypt, and the Emperor of Arabia, all different characters. (Their religion does not matter.) Once the Coptic Pope usurps the Bishopric of Alexandria from the current Bishop, he will become a vassal - however because Counts and Dukes cannot hold Dukes as vassals, he breaks the vassal contract with the Count of Alexandria and Duke of Alexandria and becomes the direct vassal of the King of Egypt, and consequently an indirect vassal of the Emperor of Arabia.
In a similar example with the Ecumenical Patriarch and Constantinople, he would instead be the direct vassal of the Emperor of Byzantium instead of the King of Greece, as Kings cannot vassalize Kings.
Mending the Great Schism
If all five seats of the pentarchy; Constantinople, Rome, Jerusalem, Alexandria, and Antioch; are controlled by Orthodox bishops whom are all, along with the religious head, vassals (direct or indirect) of an independent ruler of the same religion, this liege has a decision to mend the Great Schism. This gives all Catholic characters the opportunity to convert to Orthodoxy and makes Catholicism and its heresies into heresies of Orthodoxy. This will not happen to Miaphytism or Nestorianism, however, likely because these branches of Christianity broke off before the Great Schism.
Iconoclasts, Paulicians, and Monothelites can also mend the schism if one of these heresies manages to replace Orthodoxy as the parent religion. Bogomilists, having no religious head, cannot mend the schism. Miaphysites, Nestorians, and their heresies, though they use the same mechanics as Orthodoxy, cannot mend the schism either.
Even though the Iconoclast, Paulician, and Monotheilite Patriarchs can mend the Schism if they are orthodox, the Schism cannot be mended if Catholicism is heretical. This is due to the fact that if Catholicism (the entity that caused the Schism) is heretical and replaced by one of their heresies, there is no longer a Schism to mend.
Unlike Papacies and Patriarchates, which mainly hold religious authority and are usually regional secular powers at best, caliphates are often large feudal lands ruled by noble lords. This means one can play as the Caliph and call Jihads against enemy religions. There are a total of four createable Caliphs in the game, one each for the Sunni, Shia, Ibadi, and Karijite religions. There are also two "shiekdoms," which are weaker than Caliphs. The Yazidi and Hurufi religions have shiekdoms.
There are generally more advantages to being Caliph than disadvantages. First, you obtain CBs that can take Kingdom-tier territories from any character, so long as you either border the kingdom or own land in it. (Caliphal Subjugation for characters of the same religion, Muslim Invasion for everyone else.) You also have the ability to call great Jihads, which upon success both increase your religion's Moral Authority and potentially give you large amounts of land. The only disadvantage is that your character's Diplomacy and Piety count for your religion's Moral Authority, so if your character is impious or antisocial you may have hard time converting and heretics will pop up more often.
While the papacy and patriarchate always exist, the caliphates function as regular titular feudal titles and are destroyed if their holder becomes unlanded. However, it is possible for a Muslim ruler to recreate the caliphate. The title may be created through the regular Create Title interface, but has special requirements:
- Shia, Sunni, Ibadi, Karijite, or Hurufi (as appropriate)
- 1000 Piety OR Sayyid trait (male-line relative of Mohammed) OR Mirza trait (son of a Sayyid mother)
- (1000 Piety AND Sayyid trait) OR (control Mecca AND control Medina) OR (control Baghdad AND control Damascus AND control Jerusalem).
Getting the Sayyid trait into a dynasty requires matrilineally marrying non-Muslim men with the trait, since Muslims cannot marry matrilineally.
The Yazidi heresy also has a religious head, however it only requires 1000 piety and the de-jure capital county of Mosul.
The Yazidi and Hurufi caliphs are called "shiekdoms," and cannot call Jihads or subjugate characters of their religion. However, the Sunni, Shia, Ibadi, or Karijite religious heads are called "Caliphs" and can call Jihads - even against their parent religion or heretics of their religion. (This means that Ibadi and Karijite Caliphs can Jihad each other.) They can also subjugate characters of their religion, meaning that they are often the sole realm of their religion.
With The Old Gods DLC, Zoroastrians can restore their ancient religion to prominence by retaking the Persian Empire and appointing a Moabadan-Moabad (Priest of Priests) who will function thereafter as a religious head. A notable feature of the Moabadan-Moabad is his ability to call Great Holy Wars without having to wait until the 11th or 12th century like Christians, Muslims or Reformed Pagans.
Reforming Pagan Religions
It is also possible in The Old Gods to reform Pagan religions. The ruler who forms it and his vassals, demense, and courtiers will automatically convert, other rulers have the option of conversion. This has the following effects:
- The old, unreformed religion has "old" in front of it, showing that it's the unreformed version. e.g. "Old Tengri".
- The religion becomes organised, getting a permanent +20% moral authority, which makes conversion of others easier and makes them less prone to conversion to other religions.
- The religion gets a head. This is a duke-tier vassal like an Orthodox Patriarch, except the Germanic Fylkir who is a secular ruler like the Muslim Caliphs. The leader can call Great Holy Wars (which are Crusades with a different name), so long as both Christian Crusades and Muslim Jihads are unlocked. Once a Great Holy War has been unlocked for one Pagan type, they are unlocked for all Pagan types.
- If the Player has the relevant DLC, the reformed faith gets a Holy Order. The Germanic Jomsvikings require The Old Gods, the Zunist Sun Warriors require Charlemagne, and all others require Sons of Abraham. Note that you require The Old Gods to reform the faiths in the first place.
- Rulers gain access to the Holy War casus belli.
- Rulers lose access to the Subjugation casus belli.
- Religions that get a defensive attrition bonus (all but Tengri and Aztec) lose it, but holdings keep their levy/garrison size and strength bonuses.
- Feudal rulers may set Crown Authority higher than Low.
- Tribal Pagan rulers do not receive opinion penalties from Reformed Pagan vassals, can have Gavelkind succession (along with Elective Gavelkind), and may settle to either feudalism or a Merchant Republic.
- Feudal rulers may use succession laws other than gavelkind (and ultimogeniture for Mongols).
- Independence wars no longer have increased ticking warscore, making them harder to win. This is bad for vassals, but good for rulers.
- The "short reign" opinion penalty returns to its normal level (50% higher than other religions when unreformed).
- Germanic, Tengri, and Aztec rulers lose the prestige penalties for being at peace, but gain the usual opinion penalties for raising troops.
It is possible to reform any of the Pagan religions except the generic Pagan and Hellenic religions. This requires 750 piety and either owning all five Holy Sites or owning three and having 50% moral authority.
A Jew who restores the Kingdom of Israel can, by decision, reinstate the office of Kohen Gadol, or High Priest. Like the Zoroastrian religious leader, the Kohen Gadol can call Great Holy Wars as soon as his office is reinstated.