Factions

The realm factions screen (F8)

Factions are organized groups of vassals, united against their liege for a common purpose.

When a leader thinks the faction is powerful enough, they can issue an ultimatum to their liege. Unless the liege folds to the demands, this results in a civil war, where all faction members revolt together under a temporary title.

Each vassal can lead or join up to two Factions. If a faction leader dies, the most powerful remaining faction member automatically takes over as the new leader.

• For liege strategies, see Distribution of power guide.
• For vassal strategies, see Joining factions.

Who can join factions

Vassals cannot join factions if:

• Is a child
• Is Incapable 
• Is Imprisoned
• With liege: "Discouraged from Factionalism" opinion modifier (-5 opinion, 10 years) (from Spymaster "Scheme" mission or Intrigue focus)
• With liege: non-aggression pact
• With liege: blood oath (only affects nomads; claim-for-other factions are excepted)
• Liege of liege has outlawed vassal infighting using medium crown authority or realm peace
• Council member, council is empowered to vote on war declaration, council is content (no recent tyranny or succession), and council member is not tribal or nomadic.

Faction strength

The relative strength of a faction is estimated using the following formula:

( ( sum of member troops * 2 ) / ( sum of liege troops - sum of member troops ) ) * 100

Players receive a "Dangerous Factions" alert if a faction reaches 70% strength. AI leaders may issue ultimatums with a minimum of 75%, with large boosts to likelihood at 100% and 150%.

Faction leaders do not take into account: the actual relative army sizes (after removing their liege levy contributions), relative troop quality, or reinforcement rates. This can work to the liege's advantage, as factions do not fire when they actually have enough power, or conversely when they fire with insufficient power and are easily crushed.

List of Factions

	Faction	Notes
	Install [Character] in [Title]	Character must have a claim or an elector-rank title (under feudal elective) Attacker may call external allies (but not vassals of their former liege) If the revolt leader is also the claimant, uses a modified CB that allows the war to continue under an heir
	Succession by Primogeniture in [Title]
	Succession by Seniority in [Title]
	Succession by Gavelkind in [Title]
	Elective Monarchy in [Title]	Without Conclave and up to version 2.5.1, required lowest crown authority (Autonomous Vassals). This was fixed in patch 2.5.1. With Conclave, has no law requirement, but the Oust Ruler faction is often used instead
	Oust Ruler	Requires Conclave. Liege must be at least king tier, feudal/iqta, and not a religious head. Deposes the ruler in favor of the most popular vassal who is eligible (count+, feudal, adult, not imprisoned, not incapable , not in hiding  or in seclusion, not eunuch , and must be male unless succession is fully equal) Enacts two council voting powers Enacts "full council authority" Changes succession to gavelkind or feudal elective (using elective only if council has all voting powers, or already elective) Sets "vassal wars" law to "allowed"
	Lower Crown Authority in [Title]	Not available if Conclave DLC is activated Higher priority at higher levels of crown authority
	Increase Council power	Requires Conclave Enacts two council voting powers Higher priority at low levels of council power
	Independence	Different rules from directly declared wars of independence. Priority increased by various conjunctions and disjunctions of: distance (100, 200, 300, 400), different religion/culture, not de jure, king tier On success, every faction member gains independence.

Factions and Membership Multipliers

The following includes most of the multipliers used by the AI when deciding whether to join a faction. It does not feature the multipliers that the AI considers when initially creating the faction.

Traits

• Proud (1.5x), Brave (1.5x), Arbitrary (1.5x), Envious (2x), Greedy (2x), Impaler (2x), Deceitful (2x), Ambitious (4x)
• Content (0.01x), Imbecile (0.01x), Inbred (0.1x), Craven (0.1x), Slow (0.2x), Kind (0.5x), Charitable (0.5x), Honest (0.5x), Humble (0.75x), Just (0.75x)

Opinion of Liege

• Succession Factions: >75 (0x, if in faction - to leave)
  • Succession: >50 (0x, if not already in faction)
  • Succession: >25 (0.2x)
• Crown Authority Faction: >50 (0x, if in faction - to leave)
  • Crown Authority: >25 (0x, if not already in faction)
  • Crown Authority: >5 (0.2x)
  • Crown Authority: <-10 (1.5x)
  • Crown Authority: <-50 (2x)
  • Crown Authority: <-75 (4x)
• Independence Faction: >80 (0x, if in faction - to leave)
  • Independence: >60 (0x, if not already in faction)
  • Independence: >40 (0.5x)
  • Independence: <0 (1.5x)
  • Independence: <-50 (2x)
  • Independence: <-75 (4x)
• Claimant Faction: >25 (0.2x)

• Level of Crown Authority:
  • Crown Authority: 1 (0.1x)
  • Crown Authority: 3 (1.5x), 4 (2.25x)

Distance

• Independence: Vassals lower tier than Kings who have the same religion (or religious group, if the vassal shares culture with the liege) and culture (or culture group, if vassal shares religion with the liege) as their liege, and who are less than 200 distance away from the capital (0x)
  
  • Independence: <200 distance (0.1x)
    
  • Independence: >300 distance (1.5x)
    
  • Independence: >400 distance (2x)
    

Religion or Culture

• Independence: Same Religion and Culture (0.25x)
• Independence: Different Religious Group (2x)
• Independence: Different Cultural Group (1.5x)

Claimant faction membership

The key factors are opinion of liege, and opinion difference between the liege and claimant.

Will not join claimant faction:

• To install women over 40
• To install a parent of the current ruler
• To install someone else who has a claim on their titles (and could thus revoke without penalty)
• To install someone of a different religion
• To install someone who is blinded, eunuch, incapable, imbecile, or inbred
• To install themselves, if they are the current heir and the title does *not* use feudal elective succession
• If same religion and culture as liege, will not replace a dynast with a non-dynast
• Against their spouse or child

Claimant factors:

• Women: 0.7x (except when a woman is considering a faction to install herself)
• Children: 0.5x below each of 13, 10, or 5
• Self: 3x
• Same society: 5x (does this include themself?)
• Dynasts: 1.5x
• Born in the purple : 2x for claimant, 0.5x for liege (when the title is Byzantine Empire and the character has byzantine culture)
• If both the current liege and the claimant are Muslim:
  • Sayyid : 2x if claimant is Sayyid and liege is not
  • Mirza : 1.5 if claimant is Mirza, and liege is neither Sayyid nor Mirza

dynasty_realm_power and the title's "conquest culture" (if any) also play a role.

Characters

Personal attributes

Attributes • Traits • Piety • Prestige • Culture • Religion • Dynasty • Nicknames • Opinion

Actions

Diplomacy • Decisions • Education • Marriage/Breeding • Regency • Favors

Objectives

Factions • Ambition • Plot • Focus

Infamy

Assassination • Tyranny • Banishment • Execution • Imprisonment • Title revocation • Bribes

Other

Council • Courtiers • Disease • Succession • Alliances

Warfare

Troops

Levies • Retinues • Mercenaries • Holy orders • Event troops • Hordes • Adventurers

Battles

Combat • Combat tactics • Commanders • Raiding

Concepts

Alliances • Casus Belli • Claims • Crusades, jihads and great holy wars • Factions • Attrition