Upon death, the player would play as the eldest son, as he is the one inheriting the primary title. The other siblings will remain your vassals, unless the ruler was holding other titles with same rank as primary title, in which case holder will become independent.
Gavelkind is probably the most difficult succession law to master, as it requires some knowledge to benefit from its advantages, without suffering too much from the increased risk of succession crisis and the sometime frustrating repartition logic.
- Allows for +30% demesne limit, allowing to be stronger and less dependent upon vassals. Due to rounding, this is most beneficial for bigger demesnes and more advanced legalism.
- Has no Crown authority requirements
- Is the only law available for Pagans until religion reformation, except for Mongols, who can also use ultimogeniture.
- Prevents the prestige penalty normally incurred for having unlanded adult sons
- Prevents granting more than a single county to the eldest son
- Cannot destroy titles (except titular titles) if any held title is gavelkind
- Gives other heirs a claim on the primary title in addition to inherited land titles, so succession crises are more likely to occur.
A ruler under gavelkind succession will face the following opinion modifiers:
|Child who is primary heir||-5||They would certainly prefer primogeniture!|
|All other children set to inherit||+15||Almost certain of getting something out of the succession.|
|All other dynasty members||+5|
|All vassals||+5||A divided realm increases their own dynasties' future prospects. Vassals like decentralized and weak states in general.|
The equal repartition of land is flawed by the fact a vassal can only have one liege in the game. So due to intermediate Duke/King titles, it results in both titles and land both being unequal.
The exact algorithm is unknown, but:
- Each eligible child receives one title in birth order until all children have a title, at which point it wraps back around to the oldest.
- If one title is higher in rank than others (only one duchy, multiple counties), then the younger children become vassals of the main heir. The junior heirs gain claims on the main heir's title; the main heir gets no such claims on his junior siblings.
- Titles given out prior to succession are taken into account. A child given 3 titles already sits out three rounds of inheritance.
- As of patch 2.3.4, children who would inherit only an empire, kingdom, or duchy title but no counties are automatically given the de jure capital county of the top level title to ensure that they qualify to inherit. Also, any baronies that are not county capitals are now distributed in order to make children eligible to inherit.
- Titles are weighted by their rank. The game tries to give out empires then kingdoms then duchies as evenly as possible.
- The game favours titles being given out into politically logical portions. If multiple duchies and multiple counties in a duchy are inherited, the game tries to prevent dividing duchies or higher as much as possible.
- The game favours giving the most powerful (in terms of levy strength) titles to older children, all other factors being equal. The capital county of an independent nation has a +50% levy strength bonus, making it most likely to go to the eldest.
- Nobles of the same rank cannot be vassals of one another.
- If the ruler's titles are of equal rank and vassal of a higher-ranked ruler, they become distinct vassals; i.e. multiple duchies will be divided among multiple heirs who will all become vassals to the same king.
- If the ruler's titles are of equal rank and he was independent, his realm will be split into independent realms among his heirs.
- All children gain strong claims on one another's titles if there is a split like this, allowing for bloody reunification wars.
- Vassals go along with whichever title they were vassalized to. This usually means counties going with their duchy, but the primary duchy will usually inherit vassals from incompletely controlled duchies.
- All gold and retinues go to the main heir, giving an advantage in reunification wars.
- This forum thread claims to have cracked the title division algorithm in more detail.
To give an example, if a duke has 3 duke-level titles, but only 2 actual counties, an eldest daughter and then three younger sons, then only the eldest two male children inherit under agnatic-cognatic gavelkind. The older son gets two duchies and a county; the middle son gets one duchy and one county; the third son gets nothing because he cannot inherit any higher titles without at least a county; and the daughter does not inherit anything because she has brothers. If the two counties are in different duchies, then the oldest son gets the duchy with the county that has the largest levy, and the younger inheriting son gets the duchy that has the remaining county. The younger inheriting son is no vassal to his older brother because they are of equal rank. The youngest son and the daughter remain courtiers of his oldest brother, provided they were courtiers before.
To prevent "cheating", you cannot give out titles to your successor that they are not already going to inherit. This prevents giving them titles to a duchy you would prefer they have. If you want to give your own successor a specific title they currently are not inheriting, you will have to give away titles you don't mind giving up to other inheriting children to free up a title, or else find a way to disinherit another child. This can be circumvented in non-Muslim nations by disinheriting children through assigning them to the priesthood (which makes them ineligible for inheritance), or by finding a way for your child to die. You cannot plot against your own children, but your sons can plot against each other, and leading armies at war or proselytizing to pagans is dangerous work.
Baronies can be given to the eldest child, giving a potential leg-up in a succession war, but they also tend to be given away to vassals by the AI as soon as you give it to them.
Gavelkind behaves the same as primogeniture if there are not enough children for titles to be divided. For example, under agnatic-cognatic gavelkind, if a ruler with one son and several daughters dies, all titles will go to the son.
The effects of Gavelkind splitting up powerful nations is most easily seen in The Old Gods, with what is effectively all of continental Western Europe but Hispania being shattered into warring realms by the Karling family's inheritance. If few rulers have sons, they inherit into a single all-powerful empire (a combined Holy Roman Empire, Italy, and France) but if they have many sons, they will be locked in perpetual succession wars.
Arranging to have a single heir
Disqualify younger siblings from inheritance:
- Send them to monastery
- While they are not heirs to any title, e.g. while your demesne only has 1 holding
- Or while you have them imprisoned, perhaps after excommunicating them
- Send sons to a holy order
- Unless you're pagan or Muslim, making them bishop of a church holding title will disinherit them. You are not allowed to disinherit your primary heir in this manner, although you can do it to your heir's heir. They may have the opportunity to become Pope, increasing dynasty prestige. In case your heir dies unexpectedly, you can revoke the church title of one of your other sons to put him back in the line of succession.
Kill unwanted heirs:
- Imprison and execute (generally results in tyranny and kinslayer )
- If you're in the Byzantine culture group, you can castrate them instead, avoiding Kinslayer and tyranny at the cost of a large opinion penalty. Eunuchs can't be given or inherit landed titles. Do this before they have children, otherwise they will inherit instead. (needs verifying)
- Send your sons to lead the troops, and try to get them killed in battle or by disease.
Consider trying to have fewer children:
- If you are male, marry an older or less fertile woman.
- If pagan, Hindu, or Zoroastrian, don't take concubines.
- Imprison your spouse once you have an heir.
- Consider not having children at all, and allowing your titles to go to another branch of the family. Gavelkind reverts to primogeniture if there are no eligible children.
Sire bastard children:
- If Way of Life DLC is activated select the seduction focus.
- Select people with good genetic traits that are close to you.
- Use the "Find Characters" menu to find them.
- Lustful characters are usually swooned with more success.
- Repeat one-night stands by choosing to "love and leave".
- Wait three months and check if you or your target have been successfully impregnated, if not then seduce them again.
- Do this with as many people as you like.
- Usually three is sufficient.
- Have many children to increase the odds of having babies with good genetic traits.
- Don't forget to actually acknowledge them as your bastard.
- Legitimize the best one.
- Optional: Choose not to marry in order to avoid "Unfaithful Lecher" -100 opinion maluses with your spouse. Marry after you have selected a heir.
Organizing the division
Titles given out before succession still being taken into account for repartition, for instance giving out Duke titles of some smaller/further duchies to other sons allow to make sure your heir will inherit that big center capital duchy in addition to the kingdom.
This is best suited to aggressive expansion play-style, where conquered lands can be given out without lowering your own demesne.
Don't use the decision to have your chancellor hand out titles; do it yourself instead, even if you have hundreds of surplus titles. This decision has a habit of distributing them to your sons in a way that leaves your primary heir with nothing but your primary title and a single county, making a succession war all but inevitable.
Keeping a single primary title
Avoid creating additional kingdoms until you are ready to form an empire. If you find yourself with a second kingdom, try to "destroy" the extra kingdom by giving it to a count when few duchies will go with the kingdom:
- The duchies are not formed
- The duchies are held by you
- The duchies are held as secondary duchies
- The dukes are direct vassals of a king who is your vassal
- The dukes are at war (e.g. with each other, or in a crusade)
Alternatively, ensure your primary kingdom is the strongest, and push your claims against your siblings after succession.
Preventing succession crisis
Because your siblings inherit land and have a claim on your primary title, they are likely to create claimant factions. You (the primary heir) most likely have low prestige, a shrunken demesne, and (especially if you're unreformed pagan) a "short reign" penalty with most or all of your vassals. Between your siblings' power and your lack of power, bloody civil wars are likely.
Some possible strategies:
- Many weak heirs: it may be easier to deal with many weak heirs that may fight against each other, rather than one strong brother that can challenge your power simply by himself.
- Strong capital: A primary heir is likely going to get the capital county, so researching technology, constructing holdings and buildings can ensure said heir an advantage over their siblings. Due to de jure preference, the primary heir will also likely keep the duchy and even kingdom that contains the capital, if in a kingdom or empire.
- Inheritance of gold: the wealth of a ruler is not divided on gavelkind succession, which can be used by the heir to smooth the transition (bribes, mercenaries, ...)
- Retinues and outlying vassals: Retinues are not divided up but all go to the primary heir; and the only direct vassals your siblings get are the de jure ones. A large multi-part kingdom can conquer many duchies outside of a full kingdom, and the vassals there will be compelled to send troops to your reunification war. A large retinue on the border can strike opposing armies before they can organize, if fighting a reunification war is necessary.
- Prepare opinion boosts for your heir to use as soon as he takes the throne.
- Leave some duchies uncreated, so your heir can get prestige and "granted a duchy" opinion bonuses. (This may not be possible if you're close to your vassal limit.)
- Leave some counts as direct vassals, so your heir can transfer them to dukes
- If pagan, keep loot aboard ships for the prestige bonus.
Appointing temporary vassals
Grant your extra counties and duchies to men who do not (and will not) have heirs. Their titles will not count as part of your demesne to be divided by gavelkind, but will eventually return your primary heir -- along with any unspent wealth and tech points.
The temporary vassal should be kinless, old, and less fertile: homosexual , infirm , incapable , inbred , leper , mangled , or celibate . Betroth him to an infant girl, making it difficult for him to have children, especially if his religion does not allow polygamy or concubinage. If you are Greek and control your religious head, you could even excommunicate him, and after giving him the title, imprison and castrate him.
Combining succession types
If you hold multiple titles for which you can change the succession law, for example an empire and a kingdom, you can set the highest title to gavelkind and all other titles to primogeniture. This grants the benefits of gavelkind succession (+30% demesne, no prestige penalty for unlanded sons) without causing title splits (provided that all titles lower than the rank of king are located within the de jure kingdoms that you set to primogeniture).
The flaw in this method is if you have multiple potential heirs and your firstborn has a similarly eligible child and then dies. Gavelkind gives priority to younger siblings, and primogeniture prioritizes grandchildren, o the empire and kingdoms will split.