Playing as a vassal
As a vassal in CKII, you are protected from external attacks, but you have other concerns and duties.
Liege tax and levy costs
Remember that as a vassal, you pay taxes to your feudal liege on a monthly basis. If your feudal liege goes to war and raises your levies, you'll have to pay for them as well. If you're tribal, you don't pay taxes to a tribal liege and you join your liege's war as an ally. This means that you technically can accept your liege's call to arms, but only contribute a bare minimum to the war effort, e.g. by only raising a county's worth of levies.
As a vassal, your military is weaker than independent rulers of the same size and rank. Independent rulers get a +50% bonus to levies from the capital, and +25% bonus from their capital duchy if they're a duke or above. As a vassal, you get no bonus levies from your capital as a count, and a reduced bonus of +25% from the capital and +15% from the capital duchy if you're a duke or king. Thus, unless you have other factors in your favor, concentrate on expanding within your liege's realm, especially if you're a vassal count; securing that first duchy title would help you greatly.
As a vassal count, becoming the duke of the duchy your county belongs to is a step up in terms of military power. Beyond that, becoming a grand duke will give a +1 bonus to your demesne limit before modifiers. A grand duke with complete control of the capital duchy (and the second duchy belonging to the same de jure kingdom as the capital duchy) is in a relatively strong position for greater ambitions. Of course, before this stage, you might want to settle your succession laws.
Exclusive to Catholics
If you are playing as a Catholic count or tribal leader, consider converting your bishops to another branch of Christianity so that you can reliably secure tax and levies from them and at the same time not draw unwanted attention from your liege. You can do this by converting your character and then either demand conversion or incur tyranny by revoking bishoprics.
Another alternative is to use the Theology focus for long periods of time. It gives +20 to clergy opinion, and grants access to events which allow the character to gain good traits and Piety.
Expanding within liege's realm
- Take note of your liege's titles, especially if your primary title is not a de jure vassal; you certainly do not want to trigger the "Desires (de jure title)" or "Wants control of (de jure title)" negative opinion modifiers.
- Fabricate claims by using your Chancellor or via plots; use strategic marriages to secure claims for your relatives and kinsmen.
- Request claims from the Pope, especially against children or female rulers. Theology focus (and pilgrimage), joining a monastic order or Buying Indulgence will usually be sufficient for acceptance, as well as placing your Chaplain on the Pope's location.
As a vassal, if your government type is the only reason why you can (potentially) raid, your liege's government type must allow raiding as well. Vassal tribes who cannot raid due to their culture or religion must have a tribal or nomadic liege in order to raid. Thus, Anglo-Saxon tribes under the Petty Kingdom of Northumbria in 769 cannot raid unless they become independent, but Swedish Pagan tribes under the Catholic king of Sweden in 1066 can raid, provided they stay Pagan. If they convert to Catholicism, then they must become independent in order to raid.
Defending your liege
You may voluntarily raise your own troops to aid your liege in wars. This may be in your interest, e.g. if your titles are at stake. You can help by:
- Occupying settlements
- Helping fight battles, e.g. by linking your army to your liege's army
- Fighting your own battles, especially after offering to join the war so these battles count for warscore.
You can create or join up to two factions.
You will be the leader of a faction if you create it, or if you are the most powerful member when the leader quits. Being a faction leader has significant advantages:
- You can judge the best time to send an ultimatum. AI leaders might fire the faction as low as 75%, or neglect to fire the faction when an opportunity arises.
- You can wage war more effectively.
- For some faction CBs, including claimant factions, the attacker can call external allies.
- You can recruit faction members using a spymaster mission, Intrigue focus, or favors.
- With the latter two methods, you may be able to avoid creating the faction until you are ready, thus avoiding attention from your liege's spymaster. However, there is a risk that someone else will create your preferred faction and you will not be able to lead it.
On the other hand, being a non-leader member:
- Avoids holding a temporary title, which severely limits diplomatic actions.
- Limits the punishment for failing (one title revoked instead of two).
- Lets you double your troop contribution to the revolt: When the revolt starts, the faction leader will raise a large levy from each member (at least equal to the member's available troops). This doesn't reduce the number of your own troops, allowing you to raise additional troops for the cause.
AI rulers may fold if faction power is at least 100%, letting you both avoid a costly war. They are more likely to fold at 150%, 200%, and 300% power. They are less likely to fold for each of Strong /Brawny , Brave , Proud , Envious , Greedy , Wroth , or Ambitious . They are more likely to fold with each of the opposite traits. Finally, they are less likely to cave to attempts to usurp their titles.
If you are the most powerful faction member in the realm, your liege is likely to send their spymaster to your capital in the hope of forcing you to stay out of factions. If they are successful, you will be forced out of factions for 10 years (Discouraged from Factionalism). This cannot happen if the spymaster is busy or if you are the spymaster.
With Conclave activated, being a council member may prevent you from joining factions. If this is a problem, you can resign from the council (except as regent). On the flip side, being a council member in the immediate aftermath of a succession is a great window to fire factions or push through laws which favor you.
War against a liege
Any war against your liege will mark you as "in revolt", preventing you from declaring other wars. Some wars, including all faction wars, also give you a "temporary title" of the same tier as your liege. While you hold a temporary title, most diplomatic interactions are disabled.
Some wars can be directly declared against a liege, without using a faction. Notable among these are:
- Press claim, which uses the faction version of the CB, giving you a temporary title
- Press all claims, which does not give you a temporary title
- Independence (see link for differences from the faction version)
- Decadence usurpation
Unlike sending a faction ultimatum, declaring war on your liege does not require being at peace. This makes it more feasible to build external alliances before going to war with your liege.
Gaining liege titles
There are several possible approaches to gaining your liege's primary titles:
- Claim liege titles.
- You can use the "Fabricate Claim on Liege" plot if you are a direct de jure vassal.
- Focuses such as Carousing and Seduction can help gain supporters for the plot.
- With the Intrigue focus, you can make your liege less liked in several ways: -10 from vicious rumors, -25 from publicly humiliated, and up to -30 from councilors, while oubliette reduces diplomacy skill. Imprisoning your liege also gives you a chance to gain a favor, which can be used to become spymaster for increased plot power.
- It may be possible to install a claimant who has low intrigue and is disliked by other vassals.
- You can get claims for your heirs by marrying your liege's relatives into your family.
- Your chancellor may be able to fabricate a claim on a duchy or in special cases a kingdom. Even county claims can be effective by allowing you to declare a Press All Claims war.
- It is possible to faction to install yourself without a claim if you are an elector-rank vassal under feudal elective. You can force feudal elective through several types of factions.
- You can use the "Fabricate Claim on Liege" plot if you are a direct de jure vassal.
- Faction to oust the ruler.
- If you are the "most popular vassal", this makes you king or queen in one step. You can often become the most popular by sending gifts to other vassals (including baron-tier) or by disqualifying other contestants.
- If you are not the most popular, this faction can still be useful, by forcing elective succession (if council power is high enough) and replacing your liege with someone you don't have a truce with.
- Be elected peacefully.
- A good time to try to get yourself elected is when the ruler starts having children. Rulers are strongly inclined to nominate their own children, while vassals are inclined to vote for adults.
- If you see the election in your favor, murder your liege before it swings another way!
- Inherit the title through fallback. If you murder your liege's entire family, one of the highest-tier vassals will inherit.
- Expand internally to control half the realm. Then you can demand independence and peacefully usurp the title. This won't transfer control of your former liege's other vassals to you, but they'll be likely to accept peaceful vassalization requests. This assumes that everyone is of the same religion. If the other vassals are not of your culture, peaceful vassalization may not be possible.
Joining the council
- Doubled plot power against liege, more if spymaster
- Can be used for assassination or for plotting to claim your liege's title
- May offer to help with liege titles if your liege is over demesne limit by 4.
- Must be chancellor, steward, or spiritual. Must not be slothful . Liege must not be nomadic.
- May select yourself as the recipient if greedy , ambitious , envious , deceitful , or arbitrary
- With Conclave: opportunities to gain favors
- Favors from your liege can be used to start a law vote, request a claim war, or request a different position on the council
- Favors from fellow council members can be used to force them to join your factions (if they can join factions despite being on the council!)
- Without Conclave: gain +1 in the relevant skill, by selecting the appropriate "become councilor" ambition when your liege offers you a position.
- May become regent
- Monthly prestige (chancellor, marshal, steward) or piety (lord spiritual)
- As spymaster, your liege cannot discover your plots, except through blabbing or intrigue focus
- As spymaster, your liege cannot use the Scheme mission to force you out of factions
- As marshal of the Byzantine or Roman empire, you are eligible for the imperial throne, due to imperial elective. As any councilor, you qualify as an elector.
- If the "War Declaration" council law is passed, and your government is not nomadic or tribal, you cannot join factions unless the council is discontent.
- You may be sent on a mission to a plague-infested province. Check your location frequently! (Checking your location is also important if you are appointed as a commander by your liege.)
- As spymaster, you may be sent on the dangerous Scheme mission.
- As marshal who is wroth or steward who is greedy : you could be accused of a crime that allows your liege to confiscate your entire treasury. (The steward one is only active if playing without Conclave.)
Crown authority decreases your available demesne levies by 20% per level, effectively forcing you to leave some levy troops as extra garrison. But it also applies to your vassals: if you are a duke, crown authority forces counts to provide troops even if they dislike you.
After any succession, other vassals are likely to join factions to lower crown authority—especially if crown authority is already high, and especially if they are not inclined to join an independence faction instead. You probably want to lead this faction: you can choose whether to issue an ultimatum (depending on what you think of the CA level), and you control when and how it fights. However, if you are powerful enough, you could join the faction as a member and contribute both temporary-liege levies and personal levies.
A guaranteed way to lower crown authority is to present an ultimatum during a regency. The regent will always force the ruler to cave, even if the faction is pitifully weak.
If you intend to carve out your realm while remaining within your liege's, lowering CA to below Medium is crucial as Medium CA disables wars between vassals.
Having your titles revoked
Your liege is likely to revoke your titles if:
- Actively dislikes you (-25 or worse?) and has a valid reason, or
- Views you as an infidel (even without Religious Control law), or
- Revoking the de jure capital of their primary title, or possibly the duchy that contains it
If your liege has free duchy revocation (e.g. Iqta government), it can be difficult to keep opinion or relative power high enough that your liege does not try to revoke your duchies. Try to gain a kingdom title as quickly as possible, and then consider destroying held duchies. Alternatively, aim to become independent.
Keep in mind that if you refuse revocation, other vassals will join you in the Overthrow Ruler rebellion (roughly: those who like you more than the liege, plus your allies).
Playing in an empire with viceroyalty law
If you start in the Byzantine Empire, you may notice that your duchy title or your liege's duchy title is a viceroyalty. Viceroyalties revert to the liege (usually the emperor) on death. AI emperors can be expected to immediately select a new viceroy, usually from among the local counts.
If you are a viceroy, your first priority should be to revoke every vassal county. By owning every county in the de jure duchy, you maximize the chance that your liege will choose you as the new viceroy. Only in rare cases will your liege grant a viceroyalty to someone who holds no counties within the de jure duchy.
Once you have solid control of your duchy, you can either aim to create a new duchy or a new kingdom. Any title you create personally will be inheritable and you will no longer have to worry about losing rank on succession. One method is to fabricate a claim on a frontier county, then use it as a launching point for a holy war on an entire duchy.
If you are a count under a viceroy, you should understand that claimant factions are disabled in viceroyalties. However, you can still use the "Declare War" interaction to press a personal claim against your liege. If your parent was a viceroy, you should have a weak claim, which you can use if your liege is a child or if you can plot to make them go into hiding (intrigue-educated lieges only).
Alternatively, you might fabricate a claim on your liege's capital. If your liege has no other land and no vassals for an emergency-usurp, the duchy title will be destroyed. You can then create the title again as an inheritable (non-viceroy) title, as long as the emperor doesn't beat you to it!
Playing as a vassal king
As a vassal king under an empire, you gain access to a unique mechanic: de jure shift. Occupy whole duchies and allow them to assimilate into your kingdom. If your liege emperor holds a kingdom, shifting duchies from that kingdom to your own weakens the emperor as well. This strategy takes a long time, but can be useful should a player prefer to remain as a vassal.
As a vassal king (or a direct vassal) under the Byzantine and Roman Empire, note that you can potentially inherit the imperial title if you're not mutilated and is the empire's Marshal or commander.
Lowering your opinion of your liege
When your opinion of your liege is low, you can escape paying taxes or paying for liege levy maintenance. However, if the low opinion goes both ways, you may run the risk of having your titles revoked.
- Convert to another religion and become zealous (one-way for the -25 opinion due to "zealous"; if your liege regards you as a heretic or infidel and is also zealous, be careful!)
- Convert to another culture (two-way)
- Become ambitious and activate ambition opinion (one-way); do not become Content.
- Take on traits that conflict with your liege's traits (mostly one-way; remember that your character having good traits is more important than inducing this conflict.)
- Join a faction and wait for your liege's spymaster to force you to stop (-5 opinion: "Discouraged from Factionalism") (one-way)
- Reduce general vassal opinion: Assassinate your liege or liege's chancellor; excommunicate your liege if possible; Byzantine emperors and Catholic emperors who have the Pope as a vassal or have set up antipopes are immune. (one-way)
- If Conclave is activated, refuse a seat on your liege's council if you qualify as a "powerful vassal" (one-way). This also allows you to join factions freely.
- Get claims on your liege's titles (one-way)