guide to royal marriages, personal unions and claim throne. (2024)

----->This guide is meant to clarify what your options are in the 7 possible situations that can present itself when a country has "disputed succession". I want to note that disputed succession is merely a go-ahead in this game, the rest you got to do and decide for yourself. This guide is accurate and updated as patches come and go.

----->This guide is for any country in the CHRISTIAN religious group. As of 1.8, any other religious group cannot get personal unions anymore! Christianity includes Protestantism, reformed, orthodox, Coptic and of course, catholic. Note that an event introduced in 1.12 can install a Christian personal union involving two neighboring/same culture/same dynasty nations. But its rare.

-----> AIM of this thread is to explain how to get more chances of installing a personal union over a country. A personal union is like making a country a vassal. They will join any wars you get into (defensive and offensive), and help you outside of their own borders as long as you keep liberty desire in check, and you can integrate them after 50 years if you manage to keep the requirements for continuing a PU active. You can make *any* monarchy government nation of your religion into a minor PU slave, even big blobbed FRANCE. How? Read on.

----->At the bottom of this thread is a growing list of tips that all matter in this game of thrones. Even the pope is involved, and converting Mecca to Christianity. Curious? Read on then. Feedback appreciated. Thanks!

-----> I wish to thank @David the Gnome, @Ternega, @Ceilingcat and all other contributors and all the other console testers who backed my theories up, proved them wrong, and helped creating thread. Thanks guys!

I wish to thank @Gtius for making beginner youtube guides that summarize this entire thread. the links are below.

Part 1

Part 2

----->Disclaimer: some explanations in this thread will likely be complex to read first time. Feel free to re-read or ask questions, or to give feedback. Give me PM if you want to use this information in your own forum, wiki or whatever before using it, thank you.

Chapter 1: Basic diplomatic actions

There are two diplomatic actions which can lead to a personal union.

1. Royal marriage: marry the target country. If target country goes into disputed succession, you might get heir of your dynasty on their throne or a succession war IF their ruler dies without an heir.

2. Claim throne: If you have a royal marriage and same dynasty with another country and they have a disputed succession (either no heir or an heir with low legitimacy) you can take the diplomatic action to claim their throne. This will only show as option if your prestige is equal or higher then the target nation. Taking this action will give a -50 relations penalty to all countries you have a royal marriage with, including a -100 penalty with the target nation. The biggest benefit from claiming a throne is that it gives you a claim throne casus belli to force the target country into a personal union for 84% war score, rather than hoping their same dynasty king will die without an heir. Since this casus belli always costs 84% war score, regardless of size, it's one of the best ways to gain large swathes of territory for little cost.

Important side note: claiming throne of any nation will ALWAYS make you defendant in possible succession war. So if a same dynasty partner has no heir and old ruler, and you see that (example) France will be defendant versus England over Spain, then CLAIM that throne of Spain if you are same dynasty. The succession war will now be YOU versus England.

Chapter 2: Teasers for game of thrones

You can declare a 'force union' war if you share dynasty with a nation that has no heir/weak claim heir.

I force Pu'd Poland here, who had The palatinate and Muscovy as PU subjects of their own. If you force PU a nation that has PU subjects of its own, you become the new overlord of all those nations!

---->Doing this game of thrones I got multiple greater powers as my minor PU subject, and I integrated them all.. In theory you can get all greater powers in Europe as your minor PU subject, and integrate them all. But since 1.12, it will cost enormous amounts of diplomacy points, unless you take the right idea groups and unless you have max administrative efficiency .

Of course, you ALSO need *luck* for this. A ton of it. But you'd be surprised how many greater powers go to disputed succession status sooner or later. The idea is to PREY for chances to spread dynasty or to force PU, to "force" getting lucky. Yeah, getting lucky in PU game can be 'forced' by a player who plays this game of thrones. I mean that playing this game actively will increase your chances by a boatload, which gives you more chance to get a PU, and more chance to get 'lucky'.

-----> Player that posted this in the thread. @bbqftw

bbqftw said:

+ Integrated Scandinavia. Holy crap they are the worst PU slave, they can't fight their way out of a wet paper bag and I had to park 30k troops there just to kill their rebels because of reformation.
Rating this guide 10/10 A+++++ would claim throne again

Click to expand...

a rare occasion where inheritance by PU mechanic involves a relative huge nation like Provence.. In theory a nation can be up to 15 provinces big to get inherited like this, and Provence is close..

Chapter 3: General Tips and strategies to use in game of thrones

Before you read the detailed explanation on disputed succession options: some basic tips and things you must consider while doing game of thrones.

----->1. I want to note that the game of thrones in Europe is lot more complex then just disputed succession. This game of thrones is the hidden aspect of this game, that nevertheless can give you the most territory gain for a world conquest attempt with a European country. This game of thrones is so complex, and is influenced by so many game aspects that aren't obvious, that you got to conclude that paradox intended it this way. And many players completely overlook this aspect of the game.

----->2. Playing the claim throne and royal marriage game means keeping prestige at near hundred all the time. You can trade prestige to placate your vassal subjects (lowering their liberty desire) and you need the prestige to claim throne or to keep PU subjects (negative prestige gives PU subjects LD per point in negative!). Tough balance. You *have* to adapt your play style and keep conquest, liberty desire and rebels balanced. Humanism is a great idea group if you don't want rebels on your non accepted culture provinces. If you don't have higher prestige then the country you want to claim throne.. Then forget about it. If you want to claim throne of an ally you won countless wars with, this is of utmost importance! I once claimed throne at +96 prestige and target country (ally) had +90 (since he fought with me).. So watch that prestige. You can ask for 'end rivalry' in peace deals to farm prestige quick.

----->3.

----->4. *important tip*: message settings are crucial for this game of thrones. First and foremost, and this might be the most neglected aspect of eu4. Hidden popup and pause messages that you can enable, that are off by default. I'll use some self made images to explain

In message settings select "all" tab and enable the popup and pause for every herald possible for *every option" in the "to me", "from me", "interesting" and "other" categories.. You can select unpause also for each popup you get. Then you will get the popup, but game won't pause. In many cases, this isn't good idea. Like when battle starts, when army arrives and whatnot.

Then, in the window above the map buttons select your interesting countries. I usually select whole Europe, since you can't get PU over a country that isn't in your religion group. The result is that you can perfectly see when a new king comes to power, or when an event takes place that kills an heir of a country.
If you want to fine-tune the message settings without disabling stuff you don't like:

You can enable certain message types only for interesting category and other types for other. Select your interesting countries, and you will get the messages selected in "interesting" tab for those nations you made "interesting". All the other nations will go under "other" category, and you can enable/disable whatever in that tab.

As for the messages in the message box: if you click "send to log" in the message settings along with popup, you get both. But I never use the message box above minimap, as its WAY to easy to miss stuff there. But if you want to use it, set the according message types to "log". Up to you then if you want popup and pause for that message type as well. This can be handy when you accidentally click a popup away you didn't read. If its important, and if you set important stuff to show in the log as well, it will also be listed there.

You will never miss anything important happening in the world again.

Example: Enable minor and major event popup and pause for interesting countries, for any event they get. Why? *If* that interesting country has 40+ king with a regency heir for example, and the target county gets the event that might kill their heir, you can see the outcome right after. No more AI unions without you having a clue. It netted me, yet again, a pu over a greater power, England... Their king was 40+, their heir got sick, and it left me opening to RM England and install a noble of my throne. King died year after, and I used the cb gain to start force union war. It took me 14 years of loans, looming bankruptcy and sky high war exhaustion when he died, but I won. All because I started eyeing them month after month, waiting for my chance in the game of thrones.

You can then later disable the popup and pause for message types you don't like (like what country gives military access to another etc) by changing it in the popup window (options at right bottom). Some important popup you should enable for popup and pause: when armies arrive at destination, when country gets new king, major and minor events for you, and for interesting countries (prepare to read ton of stuff, you *can* disable this but you might miss out on easy dynasty spread chances when a country' heir dies due to event), diplomats arriving back home, traders arriving back home, what country gets succession war with another, when a country starts integrating a vassal and so on and so forth.

----->5. NOTE that heirs of a country *CAN* die during combat, sieging or just of natural cause AS WELL, and you will *not* receive a herald popup and pause for this. Here comes the disputed succession window in handy, to check if there's any heir dead that you missed (that a country went to disputed succession status without you getting notice from herald, I mean!) If you want to play this game: prepare to look at diplomacy of many countries frequently, or you might miss out on easy RM and dynasty spread partners!!

----->6. General Rules:

a) Player cannot be inherited. Instead, if there are no valid Contestants, then PU (otherwise SW) will happen.
b) Junior leading a PU herself cannot be PUd or get a succession war over her throne. A noble will rise either from the same dynasty (if there is one) or from RM partners; whichever is strongest. I.e. Aragon cannot be PUd while she has Naples under her. (yes, Castile can with the Iberian wedding event, but not otherwise)
Independant nations with only 15 provinces or fewer can be inherited. If they have more, the inheritance will revert to PU/SW
d) For PU or SW the size or the prestige of the Successor and/or the Contestant does not matter.
e) If a PU is contested, it will turn into an SW. An inheritance of independant nations can also switch to succession war if an eglible candidate to contest shows up.
f) If you fight a force union war, and the heirless country with your dynasty member also has minor PU countries... You will *also* get these nations as minor PU slave IF you force their overlord in a PU. As screenshot in the teaser chapter shows, I got Poland, Muscovy and a huge palatinate in one war, just because I force Pu'd the overlord.. For 980 prestige.
g) PU subjects only get liberty desire from their OWN development and army size (not from ALL the subjects combined like with vassals); they also get 1 liberty desire for each point overlord has negative prestige. 100 LD for -100 prestige. so farm prestige folks.

-----> 7

a) If Junior is at war, no PU/Inheritance/SW will happen. A noble will rise either from the same dynasty (if there is one) or from RM partners; whichever is strongest.
b) If Successor is at war with anyone but the Contestant -> instead of inheritance a PU/SW will happen.
c) If Successor is at war with the Contestant -> instead of a SW a PU will happen (the UI will display succession war...it's a bug).
d) If the Contestant is at war with the Successor -> popup will indicate the SW, you can click Go to War, but it won't work, your war will remain the same one you were in already. Thus you cannot enforce the PU under you, and the Junior won't join in the war. (also bug) You can however cancel the PU

-----> 8. I RMed an heirless country! (basics, its explained in more detail in chapter 5)

If you want to spread your dynasty, inherit/PU a country or fight a succession war for their throne, you have to start with an RM.
Pause the game and check the screen, one of these will be displayed:

a) A noble from some other house will succeed to the throne:

That other house is has more effective development than your country. You need to become stronger than them to install a noble from your dynasty. Note that spreading dynasty into a nation that has a dynasty existing in *multiple* nations (like De Valois, Habsburg, Trastemara) will require you to become bigger in effective dev then the largest dynasty member.

b) A noble from your house will succeed to the throne:

You are the strongest/most developed of the RM partners, also the country is in T0. That lasts for 75 years, even though you don't know when that has started, there is a good chance that they will be in it for quite long time. That's fine, a dynasty spread is more than good of a reward!

c) Some other country will inherit them:

That other house is stronger than your country. Get more diplomatic reputation, stability and total development/province count. Also, hope that the monarch won't die just yet so the Tier can shift to T2 (so you can contest in a succession war).

d) You will inherit them:

Fantastic! That's T1, which - sadly - only lasts for 5 years. Also, you don't know when it has started, so you better start praying harder!

e) Personal Union under your country

Awesome! That's T1 or T2, or they share a dynasty with you. T2 lasts for 20 years, chances that they will be in it for 7 or so years. Either way, best of luck to you.

f) Succession War between some other country and some other country:

Get stronger, and do it fast! If they are of your dynasty, claim their throne and you will get to be defendant in the war.

g) Succession War between some other country and your country:

They are either in T1/T2 or they share a dynasty with you or them. Either case, you can contest the PU as the Attacker, so hope for the monarch to die and prepare for the fight.

h) Succession War between your country and some other country:

They are either in T1/T2 or they share a dynasty with you or them. You are the Successor (i.e. the Defender) so it should be an easy fight.
But that state will not stay like that forever, because Tier dates will be recalculated, so you have to be a bit active. Also, RMing a country with your dynasty is not always necessary.

----->9. Okay, what should I do and when?

It's up to you. Some play aggressively, some play conservatively, use your own style I can tell you a few guidelines though. Ofc, any king can die at the age of 25 or live beyond 90, so even with the most efficient strategy, you still won't be able to beat RNG.

PU subjects are best subjects you can ever have. They will field biggest armies, have best economy, and lowest liberty desire for their development.

so you can feed them their entire culture group, and still not see the need to integrate them, providing you grow in EQUAL size. At least feed PU subjects up to their state limit.

staying at war constantly prevents them from declaring independence. Keep a rival slot if you got a rebellious PU subject, and rival whoever is supporting the independence of the PU subject. Then just declare on your new rival with humiliate CB to make PU subject lose independence support.

I'd only integrate PU subjects in age of absolutism on 100% absolutism, and ONLY the ones that you cannot inherit naturally. So, the tiny ones should never be integrated. The only reason to integrate PU subjects earlier, is TRADE. For example.. if you play Savoy and you got Milan in a PU early on.. Then it might be better to integrate Milan ASAP to stop them from leeching trade income away.

- Pray...constantly
- Check the disputed succession alert often. It is your best friend!
- Check interesting and semi-interesting countries every January at the very least. A new Tier always start on the first of January. If you can catch a change in the rules, you know a new Tier has just started. With T1 lasting for 5 and T2 lasting for 20 years, you can have a nice window of opportunity. These outcomes are hardcoded and not based on luck. However Tier dates are, so always check the age of HRE Emperor and the Pope! If they are old, chances are that they will die. Why is that important?

note: Upon death of the Emperor, and upon a new Curia Controller country, the Tier dates will be recalculated. This can screw you over ... but this can also favor you. It is just coded like this.. Don't ask ME why

- Important: if a new Pope is chosen, but the CC country does not change, then there will be no change in Tier dates.
- Junior gaining/losing provinces also shift the Tier dates, but only by -1/+1 year per province respectively.
- If a Tier is not suitable for your needs, check HRE/CC. If they are old, then the Tier is about the change. You can keep RM or just break it accordingly.
- Always re-check countries after recalculation (in January) or after they won/lost a war, maybe a new possibility has opened up.
- Consider taking Diplomatic Idea Group for the lowered impact on stability from diplomatic actions, so you can break your ROMs without the Stability hit. Note, that the countries will still hate you for doing it.
- Consider taking Espionage for the Sabotage Reputation. I haven't tried it myself, so I cannot say how effective it is, but countries are less likely to RM countries they don't like. The less competition you have, the better. Also, less ROMs, means lower heir chance!!
- Have at least 30 provinces, so you can inherit all eligible countries.
- Do NOT RM countries that already lead a PU themselves! They cannot be PUd in any way (see General Rules). They can be inherited but the chances for that is very slim, and you best use your diploslots somewhere else. That being said, if you see an olds monarch for a country with PU to be inherited by someone else, just toss an RM. Break it though once the opportunity is gone.
- Once an heir appears, consider breaking the RM.
- Rivals of the Junior can contest the PU and force a Succession War. While you cannot make the Junior to rival you, but if you rival them, they might switch to you eventually. So try to chose countries for rivals that do not rival you. The more enemies you have, the more PUs you can contest.
- Keep War Rules in mind.

Kraal Rokviente said:

Hi, I Need some advice for my current game that screwed up within 2 months. I was able to contest a PU of Russia and England and forced Russia to be my lesser union partner. As Russia is a great power Nation and around same size as mine it is a big addition to my Country. But within two months after I won the war my ally France became also a lesser union partner of me. That is great but France is around double the size of me (most of France, most of Britain, most of Spain and Portuguese provinces plus American colonies) and has a huge army I couldn't defeat if it comes to independence war. So what can I do to secure these two big unions at the same time without getting kicked by them.

Click to expand...

slap diplomat improve relations on them. get dip tech up. max diplo reputation with advisors. max legitimacy and spend mil points if needed.

farm prestige, as PU subjects get 1% ld for each point overlord is in negative prestige. -100 prestige is 100 LD in PU subject, so farm that prestige!

be at war constantly, and never be at peace for a day. Unions get -50 malus to declare independence if overlord (and them) are in a war.

If you own Cossacks dlc, you can conquer provinces near them, and then you can grant the conquered provinces with the subject window option. If the conquered provinces border them by land or sea zone, you can grant those provinces to them.
It will lower their liberty desire, and THEY got to attack the rebels that follow. Its a great way to weaken subjects.

And constant warfare (leading their armies around with 1k stack with attach on) will lower their army strength, which will all in all result in docile PU subjects.

If one of them goes above 50+% ld, then enable loyalist faction. You have to prevent PU subjects from allying, which they will do if one goes above 50%.

If someone supports their independence, then rival them and crush them with humiliate rival cb.
That's the best thing to do in 1.17. Keeping free rival slot for nations that support subject independence guarantees a CB to stomp those supporters the minute they support your PU subject independence.

-----> 10. disinheriting an heir can be quite useful. Marry a nation of the dynasty you want to obtain, and then disinherit your heir when your ruler gets old. Go to war then until your ruler dies, and a noble from the desired dynasty will ruler your nation, provided that nation is your biggest development RM partner. Note that you need to go to war until this happens, to avoid succession war over your nation! If you don't, you suddenly might end up as PU subject of France..

Chapter 4: General rule sets for entire in game mechanic

This chapter is dedicated to @Ceilingcat, who did tremendous job of delving into how some formulae in the mechanic get calculated, and how the game used some stuff to simulate some randomness into this 'game of thrones'.

Disclaimer:

If you want info only on what to do in this or that disputed succession, it might be better to skip to chapter 5, as what follows is quite complex!

When a monarch becomes heirless, one of the three rule sets will be activated: Tier0, Tier1 or Tier2. (Upon discovery I called them tiers, but now maybe Era would be a better word for them... for the sake of consistency I will keep calling them Tiers.)

In an unaffected world the
- T0 would start on 01.01.xx00 and it would last till 31.12.xx74 in every century. Active for 75 years.
- T1 would start on 01.01.xx75 and it would last till 31.12.xx79 in every century. Active for 5 years.
- T2 would start on 01.01.xx80 and it would last till 31.12.xx99 in every century. Active for 20 years.

This is a cycle, it never ends. Once T2 is over the next century would start with T0 again.

Something like this:

So if the monarch would die in 1504, the T1 rules would be active, while in 1532 the T0 would be in play.

Now, if you play a game, the above, default values are periodically shifted, so you should never know when have the currently active Tier started, or when will the next one start. You can however know (or guess) the currently active Tier and it's rule sets.

The Tier start dates will shift every time, when:

- a new HRE Emperor is crowned
- a new country is chosen to be the Curia Controller
- the observed country gets a new monarch (even Regency Councils count!)
- the observed country gains/loses provinces
- the observed country moves its capital
- AI nation creating a formable will move the tier date around due to a different ID.

So the age of the monarch is not a factor in this. Obviously the best scenario for you, if the observed country is in T1 or T2 when the monarch is old. You have very little to none influence over this

Here be dragons, erm... some advanced stuff

Suffice to say, its quite complex to calculate the tier date of the nation at this or that date. Maybe its more practical to just adapt to the succession status at hand.

What happens when a monarch becomes heirless?

Well, that depends on which Tier the monarch died!

Tier 0 (the default case):

a) no RM & no dynasty: local noble succeeds

b) RM & no dynasty:
- strongest RM member spreads her dynasty

c) No RM & dynasty:
- no valid Contestants exist: PU
- valid Contestant exists -> SW between Successor and Contestant) RM & dynasty:
- if other dynasty members are too weak -> strongest RM member spreads her own dynasty (i.e. Ryazan can't contest a dynasty spread from Austria over Muscovy)
- if at least 1 dynasty member is strong enough to block the spread -> SW between Successor and Contestant.

As said before: claiming throne will always make you defendant in succession war over same dynasty nation, even if you are smaller then the RM partners of the heirless same dynasty nation.

Tier 1 (the inherit case):

a) no RM & no dynasty:
- local noble succeeds

b) every other cases (RM & no dynasty / No RM & dynasty / RM & dynasty):
- strongest Successor will inherit if her number of provinces >= Junior's NoP * 2 AND Junior's NoP <= 15
- 2nd strongest Successor will inherit if her number of provinces >= Junior's NoP * 2 AND Junior's NoP <= 15
- succession war between them if neither qualifies for the above (even if there are more RM partners with enough NoP)
- not enough NoP and no valid Contestants exist -> PU
- not enough NoP and valid Contestant exists -> SW between Successor and Contestant

Tier 2 (the instant PU case):

a) no RM & no dynasty: local noble succeeds

b) every other cases (RM & no dynasty / No RM & dynasty / RM & dynasty):
- no valid Contestants exist: PU
- valid Contestant exists -> SW between Successor and Contestant
"Junior" is the junior partner of your future PU
"Successor" is the strongest of: Junior's dynasty members and Junior's RM partners
"Contestant" is the strongest of: Junior's dynasty members and Junior's RM partners and Junior's rivals

Note: Non-Monarchy Rivals and Rivals not following any of the Christian denominations are invalid and they will be disregarded. I.e. catholic Austria can be the Successor for the orthodox Muscovy PU, and while Muscovy's rival the orthodox but republic Novgorod cannot be a Contestant, the rival protestant Prussia can be. That's right, some republics CAN contest a succession. Dutch republic is good example.

The exact calculation for the "strongest" is not clear, but all points to the 3rd page of the Ledger. The higher the Adm./Dip./Mil. Rank & Rating, the stronger your country is. Note that the overall ranking does not seem to matter though, as you can be rank 3 but if your Dip. rank is very low, even the 5th country can get ahead of you for the Succession. Its either this, or military rating of nations. Or a mix of both. Needs some testing still.

Chapter 5: Disputed succession, what to do in each situation

There are 7 possible situations for a country that has disputed succession. All 7 can have different outcome, depending whether or not you decide to step in the game of obtaining personal unions.

A. No dynasty, no heir
B. No dynasty, weak heir / regency
C. Same dynasty, no heir
D. Same dynasty, weak heir / regency
E. succession war as defender/attacker
F. You inherit the throne
G. Interregnum

Check this link to see it in imgur image format:

Here is detailed description of what your options are in the previously given 7 situations.

OPTION A : You do not share a dynasty. They have no heir.

AIM is to put your dynasty on foreign monarchy throne to open up future possibilities, or to get succession wars over countries. Aim of YOUR nation is to gain the highest development possible; it gives your nation lot more chance to get a dynasty spread in other (greater power) nations.

Basic rule of thumb (very important!):If you become highest total EFFECTIVE development nation of all RM partners of a nation, you will deliver a noble of your dynasty to become ruler of that nation, if their old ruler dies heirless.

The total THEORETICAL development of your country is shown in the country tab of the ledger. The total EFFECTIVE development deducts the percentage of local autonomy OFF the total development value of your provinces, and then adds it all up.

I bet you say "eeeeehhh.... what?" now....

I'll elaborate.

----->The development of a province is the sum of its base tax, base production and base manpower. A country's total THEORETICAL development is the sum of all of its provinces' development values. You can see this value in the Country tab of the ledger.

So, local autonomy deducts a fair part of this number, giving the real TOTAL EFFECTIVE DEVELOPMENT. This total effective development is what determines who supplies the new king for an heirless throne, out of all RM partners. You can see the effective development of your nation if you hover over the cost of embracing an institution in the relevant window.

BUT since the autonomy of provinces is taken into account, the number is just a guideline. Anyhow, the idea is to get more development then other RM Partners of your target heirless nation. If you see another RM partner of them is delivering new noble to their heirless RM partner... Then BLOB more, or develop yourself, or lower autonomy in high development provinces that have high autonomy (in case of an almost tie in development between nations, might not be good idea overall). This will make YOUR nation the one that delivers new noble kings of your dynasty in foreign monarchies you married into.

After this rule of thumb, I'll just refer to total development as the rule, to keep it easy!

1. General advice in step A:

Check if they have an other RM. Check what will happen upon Monarch's death to get the active Tier.

---> if they have no other RM then do RM to test the waters..

---> they are in T0 & you are not allied to them:

if you can beat her alliances, then RM to get a dynasty, claim Throne ASAP and start the war. Force the Union.
if you cannot beat the alliances, still RM them but only if you don't want to expand in their territory later.

---> they are in T0 & you are allied to them:

might as well RM them as well, a dynasty spread is always nice.
Keep in mind that since patch 1.14, breaking an alliance gives 5 years of truce, so for the old 'spread dynasty-claim throne-go war' tactic you would have to break truce.

---> they are in T1 or T2

RM ASAP. Keep in mind that the tier can shift any year, and on HRE/CC change. Revaluate your strategy if needed.

Important note: It is POSSIBLE that you will get a personal Union for free, even with a greater power, if the heirless nation is in Tier 2 and IF no one contests the Union. You need luck to be in tier 2 with heirless nation for this to happen, but it IS possible.

---> they are heirless and hostile (rm not possible): if you can RIVAL the nation with ld ruler and no heir, rivaling them might trigger a succession war, where the player will get popup to contest a succession as AGRESSOR in the succession war. More details further in the guide, in chapter 5 under succession war section.

If you do a marriage with a greater power: If you start as a tiny nation in Europe, you have almost no chance to install a noble of your house on a greater power throne (since you lack high development), UNLESS you are the only RM partner of that greater power. Once you DO blob or develop (play tall), your chances to install a noble on your greater power RM partners ruler death will be lot higher. Develop your nation or expand and check if your development is higher then other RM partners of an heirless nation.

So, try to send royal marriage offers and later on "offer alliance" offers to as many greater powers in 1444 and beyond. Once you become big and have a big development, you will see your chances to install a noble anywhere rise, even in greater power nations.

Example: As Savoy I got alliance with burgundy and Austria in 1445, and with Spain and England after I got positive opinion with them thx to bashing France (their rivals) up. You can even get Muscovy as ally if you obtain a province close enough (examples are: DOW on Genoa or any Black Sea country, or DOW a Baltic Sea country like Riga in 1444).

2. To get succession wars in step A, it is VITAL that you set a powerful country as rival.

Why? Because then they can rival you back also, if they didn't already. Why is this important?

The nations that set YOUR NATION or the HEIRLESS NATION as rival can contest succession, among others( more on that later). Bottom-line is: it is usually a nation that set YOUR nation as rival that eventually contests.

England, France or a blobbed Russia will do. If no big nation set you as rival, its more rare to get succession wars in this stage.

Conclusion: Succession war is the easiest way to get free PU subjects in step A and in general (apart from getting a FREE PU with just RM done, which can happen if heirless nation is in tier 2).. so setting a powerful rival helps, cause they can then rival you back (if they didn't already).
I'll say it again, cause this is quite important: it is entirely possible to get succession wars over a country with no heir -that is NOT of your dynasty but with whom you ONLY got a RM with- IF there is a nation willing to aggressively contest the succession ( a big powerful nation like France, who rivaled you or the heirless nation, for instance) or IF the heirless nation is in tier 2.

Note that rivaling a nation without an heir might make your nation legible to CONTEST their succession in a succession war, as aggressive contestant, with the popup. More on that in succession war part of the guide.

3. Possible outcomes in step a:

a) What can be the result of all of this?:

If a ruler dies heirless in a RM partner, you get chance to get a personal union with a succession war, IF
-------->1). a country with the same dynasty as the target OR nations that rivaled YOU or heirless nation OR your RM partners OR the RM partners of the heirless nation qualify to contest you over the right to have the nation as minor PU subject AND 2). target nation must be at peace.

If no succession war triggers, the default result is that a 20 year old heirless noble, of the dynasty of the largest total development RM partner, will become the king of the target country.

b) requirements for a good outcome for your nation

-------> 1). You have higher total development then the other royal marriage partners of the heirless country and/or 2.) if no bigger greater power can contest the succession in any way, as stated above.

"a xxxxyan noble succeeds to the throne" it will say, if you look at what the outcome of succession will be, in their diplomacy window. If they produce an heir, your chances for this are removed. You may not start a war to create a union, until you are in step C

------>After a noble of your dynasty took throne you are in STEP C with that nation. you are able to claim throne and do force PU war immediately (the new noble king will start as heirless, after all)!
Prepare for that, if you wait too long, the nation might get an heir again.

c) Important notes:

------>The succession status ITSELF can shift from succession war to your dynasty noble becoming king (if you got RM with the nation), or another noble from another RM partner, if the target country goes to war... So warn all countries that can drag them in and the country itself! Usually succession wars of this type involve tiny countries that also had RM with the heirless king nation, or small rivals of the heirless king country. You will seldom see greater powers that step into aggressive wars involving small countries with disputed succession, since they don't care about forcing tiny countries into a minor PU situation with them. Situation changes if country is bigger or if the disputed country is a dynasty partner, or a rival of them. HRE emperor is exception, that nation will meddle in all succession wars inside HRE.

------>if you got 4+ royal marriages (6 total gives +10 bonus % chance of this happening!) you can get the event that places an heir of your dynasty on their throne (event is called "marriage policies pay off" link from eu3 wiki: http://www.paradoxian.org/eu3wiki/Marriage_Policies_Pay_Off and ). I have seen this event trigger for an heirless burgundy. Funny, the comment on the event says: "take that, von Habsburgs!" Very appropriate indeed, if you can stop the Burundian inheritance event this way. Note (thx Thund91) that your heir actually needs to make it to the throne, or you won't get a dynasty spread. If a noble of your house does get their throne, you officially made a dynasty!!! But I'm getting ahead of myself, that is possibility C.

-----> disinheriting an heir can be quite useful. Marry a nation of the dynasty you want to obtain, and then disinherit your heir when your ruler gets old . Go to war then until your ruler dies, and a noble from the desired dynasty will ruler your nation, provided that nation is your biggest development RM partner. Note that you need to go to war until this happens, to avoid succession war over your nation! If you don't, you suddenly might end up as PU subject of France..
but remember: farm prestige, as PU subjects get 1% ld for each point overlord is in negative prestige. -100 prestige is 100 LD in PU subject, so farm that prestige!

4. Consort mechanic strategies (thought up by @Badesumofu)

----->try to marry other countries as a new ruler comes to power. That gives you a 50% chance to get the consort. You can then look at their opinion of you and look for 'consort ties', that indicates you got the consort. Then you need that country to settle on a weak claim heir, and then you need the ruler to die before that weak claim heir is 15 - then you have consort regency of your dynasty and a weak claim heir - since you initiated the PU it will still be in effect allowing you to Claim Throne. Note that it doesn't matter what happens dynastically once you declare the war. You might get a notification that you lost your claim but don't worry, you can still enforce it in the peace.

Note that I'm not suggesting that this is a better use of an RM than simply marrying a country with a old ruler and no heir. It is just another way to possibly get a PU. You need to keep an eye on the target to see if the conditions are on their way to being met - like if they get a weak claim heir with good stats - so you can prepare. Break any alliance you have with them, try to look for how you can strip them of any other allies.

----->The other thing you might think to look for would be a weak claim heir in a country with no consort - that will be rare as any time a country gets an heir without there being a consort, a consort is generated alongside the heir. Of course consorts can die, so it might happen. You would need to establish whether or not they have a consort by looking for that opinion modifier - see if they like some other country because of consort ties. Even then, they might have a domestic consort so this method is not very likely to yield anything. The main issue here is that it is quite difficult to tell if a country has a consort or not. Hence why I aim to send the offer immediately when a new ruler comes to power since new rulers never come to power with a consort.

----->It works in both directions. Basically when the game checks to see what a country's dynasty is, it just checks the name of the current ruler. So if you are in a consort regency, you can claim throne on any nation with the dynasty of your consort. This allows you to PU, for example, Von Habsburgs without actually having that dynasty in a permanent way on your own throne. Or if you are trying for a reverse dynasty swap but you get a new heir with good stats while your ruler is 70 you can just keep them if you have the right consort since that will give you a temporary reverse dynasty swap for the regency. Also useful if you actually want to keep your own dynasty for some reason you can just temporarily borrow another dynasty to PU someone (which does not have to be the person you actually got the consort from, of course).

Conclusion: consorts open up *a lot* of new options alongside disinherit and abdicate. These new mechanics were overall a massive buff to Monarchies both in raw power potential and in how interesting they are to play.

important sidenote: if a consort regency is active in your highest development rm partner, the dynasty of the CONSORT is rigged to spread into YOUR nation or others if your ruler or another rm partner dies heirless. This is really silly, but its the rule.

OPTION B : You do not share a dynasty. They have a weak heir. Basically, do nothing in this situation, unless a consort of YOUR dynasty is regent for any weak claim heir. You can actually claim throne then, and start force PU war!

OPTION C: You share a dynasty (meaning a noble of your country took throne after their king died heirless; or a noble from your dynasty took throne after RM with third country with your dynasty (complex!)).

If a same dynasty country has ruler who dies without heir, then total effective development of dynasty partners determines who gets PU over same dynasty member.. If same dynasty partner is bigger in effective development then the RM partners of the heirless same dynasty nation, then a free PU can occur. If RM partners of the heirless same dynasty nation are BIGGER then you, then a succession war can occur as described in step A. But there is a solution for this, to become defendant in possible SW over any same dynasty nation.. Claim their throne!

Important side note: claiming throne of any nation will ALWAYS make you defendant in possible succession war. So if a same dynasty partner has no heir and old ruler, and you see that (example) France will be defendant versus England over Spain, then CLAIM that throne of Spain if you are same dynasty. The succession war will now be YOU versus England. If a smaller dynasty country has RM, same dynasty AND claims the throne, then it will switch to that country. The AI never seems to do that, but the PLAYER can.

The DEFAULT outcome between same dynasty nations is that small dynasty members become PU subject to a really big same dynasty member IF the big dynasty member has at least twice the development/number of provinces and IF the small dynasty nation sees its ruler dying without heir. More or less.

A succession war can occur too, if someone contests this peaceful transition. Succession war can occur I step A, and in step C.

But there are more options in step C.

---> If you are allied to same dynasty nation and they are heirless:

that's too bad. You would get 5 years truce if you break the alliance, so while you could start the war for the Union, but that would mean a ton of Aggressive Expansion. Consider monarch age and your situation.

---> AE is not an issue and it's worth it: go for it!

---> AE is a problem & you would get them in a PU, or Succession war:

up to your style. Personally I would wait if the monarch is old enough; and break alliance if he/she isn't likely to die soon.

---> AE is a problem & the war for succession would go without you:

oh my... break alliance, prepare for war and claim the throne once the truce runs out. It can't get worse anyway.

---> you are not allied:

I hope you don't have truce either. Claim the Throne, start the war, force the PU. Keep in mind that the claim throne option and the casus belli will go away if they get a proper heir. But once you start the war, an appearance of a new heir becomes irrelevant; you can force the PU even if the CB is gone.

Anyways, I got PM asking me questions about this situation C, so I'll give example on how you can get chance to get succession war or chance to claim throne of an heirless country of your dynasty; a country you (maybe) never had RM with. Yes, it can happen. After all, the heirless king is desperate for an heir, right? *grin*

Austria can get the opportunity to install a Habsburg on the throne of Hungary with an event. They did. A Habsburg now rules Hungary.

Lets take the example that you are Byzantium as a human player, you managed to survive vs. Ottomans, because you had alliance and RM with Poland and Hungary. Your king dies heirless. A Habsburg noble succeeds to your throne, since HUNGARY had most development of all your RM partners. Byzantium is now part of the Habsburg DYNASTY. The Habsburg dynasty spread, because you had RM with Hungary, who also had Habsburg ruler. Are you still with me?

..All goes well, you win some wars vs. Ottomans. You rake in the prestige. Meanwhile, Austria gets slaughtered by France, their prestige is dropping fast. Even the position of emperor might go to Bohemia. You now have higher prestige then Austria.

...You don't quite care as Byzantium, you got your own problems versus the infidels...
BUT (and here the plot thickens!!)...

Austria, the *emperor* of the HRE, has a 68 year old king and his 45 year old heir dies to hunting accident. Their king, of your dynasty (this is what its all about, this game of thrones) has NO heir all of sudden. If you are highest total development nation of your dynasty (the patriarch so to speak) then you can get a succession war or an instant PU over the heirless country of your dynasty, without having royal marriage! Or, you may claim the throne of Austria if you manage to secure a quick royal marriage with Austria! (shouldn't be *that* hard). You can claim the throne because you have high prestige and Austria has lot lower prestige.

if the emperor dies heirless, YOU may get chance to get Austria as a minor PU slave (with a force union war, or through a succession war, or by peaceful transition of the heirless nation into PU subject of a dynasty partner), emperor or not, greater power or not. Yeah that's right. Game of thrones!

----->If a king dies without an heir, you get a personal union, right of the bat, no war involved, if:

they are really small country with your dynasty and your total development is high enough versus theirs, and no one can or will contest the succession. Note that it is also possible you straight inherit a nation like this then, if your diplomatic reputation is high enough.

a) You got same dynasty as them, you have a lot more total development, and no nation will contest the succession outcome. You don't even need RM or Alliance; it happens automatically IF you are big enough in development versus them.

b) doing a force union war *after* doing royal marriage/claiming the throne of an heirless dynasty country. You have to start this war before they get a strong heir, or the casus belli gets removed. If they get weak claim heir, you keep the casus belli until that weak king ascends and creates strong heir of his own.

c) This can happen in step A and C... You got royal marriage with dynasty partner of anyone, but some powerful nation that qualifies (like Austria vs. England, or France vs. Spain) will wage succession war when your noble ascends to their throne. So, succession war over greater power is possible even without having dynasty (and just a rm done) with them IF your nation or the heirless nation set powerful nations as rival. As said before in option A, but I just repeat it here

d) The diplomacy window for an heirless greater power says you will get a succession war. If you are aggressive claimant (your country is listed RIGHT: XXX vs. you)you can aggressively steal the greater power away from whoever gets the greater power as minor PU subject when the king dies heirless. You will get popup if you want to start a succession war. Think carefully before accepting, as the defending nation who gets the PU can also call in all their allies.

e) The diplomacy window for an heirless greater power says you will be the defensive side (your country is listed LEFT: you vs. XXX) and you get the country as minor PU subject at the start of the succession war. Note that the aggressive claimant can back down if you are more powerful, and you will get PU right off the bat. The AI Always attacks though, even if its suicide..

f) You got same dynasty as heirless country, and you decide to claim throne after a royal marriage. You decide you do NOT want FORCE PU war. IF the ruler of the claimed throne dies heirless, you will get the PU for free. That's right. FREE!

----->Claiming throne is not needed *always*; Claim when king is young when you are confident you can do a force Union war. Do it when king is old (see below) if not. Just make sure that you got max diplo relation modifier (+100) with countries before you got RM with before claiming throne of a third country, as you will get -50 relation penalty with anyone you got royal marriage with for claiming a foreign throne with royal marriage mechanic. And -100 relation relation penalty with the country you claim on. But this malus opinion will tick away fast.

Conclusion: you don't need to claim throne whenever you can; rather wait for the best time to do so. CLAIM the throne when your dynasty noble ascends to throne in foreign nation and if you feel confident that you can win a force Union war OR if their king is 50 or 60+ and heirless.

Bottom-line is: Chances to get greater powers as minor PU slave are few , and you don't want someone else getting them under their thumb. So think carefully what the best approach is. If you are in a weak position still, without greater power allies, claim when if their heirless king is 40+ and not lucky nation, or when has few RM. If its lucky nation or if the nation has a LOT of RM, 50-60 years heirless king might be better time to claim. IF you are big and confident, just claim throne when your noble ascends to the throne and start force union war the month after you claimed throne.

Why? Cause the older a ruler is, and the fewer RM their nation has, the fewer chance the nation/ruler has to get an heir the normal way, without event. Even a 70+ heirless king can get heir the normal way....If they produce a strong claim heir after you press claim throne, your claim is removed.
Weak heirs (that usually spawn by dynastic event) will let you keep the force union CB.

You receive casus belli to start a force PU war if you claim throne while they got no heir, and you may force a union by war. If they produce a strong claim heir BEFORE you begin that war, you lose the chance to obtain the casus belli by claiming their throne. IF they produce an heir AFTER you start that force PU war, it will not matter... So *START* the war the minute someone of your dynasty seizes a throne, even if you are NOT prepared and even if it means taking a stab hit. If the target country is a greater power, this is almost obligatory. Just go all out on loans and mercenaries, these wars can be the beginning of a world conquest attempt if done before 1500.

Right. Are you still with me? I know this is heavy stuff.. Some examples now of step C situations.

----->An example of a peaceful transition: country A having dynasty with country B, country B' king dies heirless, and country B has RM with country A. If a dynasty in one country dies out, that country becomes minor PU slave to the dynasty country with highest total development of all other dynasty partners. Usually peaceful transition is done between a big country and a really small country that's close them. Example: Muscovy getting peaceful PU over Ryazan or Yaroslavl. Or god forbid, the other way around.

----->An example of an enemy of the heirless country being able to contest succession without having RM: Poland spread its dynasty to Muscovy. The king of Muscovy dies without an heir. Poland is rightful claimant, due to having RM with dynasty member, but Sweden can contest this, since they are a rival of Poland. Succession war will decide if Muscovy goes under Poland or Sweden as minor PU slave. More on succession war later on.

------>Another important note: You can get Union over another same culture/dynasty neighbor nation now BY EVENT, without a war.
Note that an event introduced in 1.12 can install a Christian personal union again involving two neighboring/same culture/same dynasty nations. But its rare.

# Offer Personal Union

Click to expand...

country_event = {
id = dynastic_events.5
title = dynastic_events.5.t
desc = dynastic_events.5.d
picture = DIPLOMACY_eventPicture

trigger = {
has_heir = no
government = monarchy
is_subject = no
ruler_age = 16
NOT = {
ruler_age = 40
}
any_neighbor_country = {
government = monarchy
has_heir = no
ruler_age = 16
NOT = {
ruler_age = 40
}
NOT = {
OR = {
has_opinion_modifier = {
who = ROOT
modifier = opinion_spurned_pu
}
reverse_has_opinion_modifier = {
who = ROOT
modifier = opinion_spurned_pu
}
}
}
OR = {
AND = {
is_female = no
ROOT = {
is_female = yes
}
}
AND = {
is_female = yes
ROOT = {
is_female = no
}
}
}
OR = {
dynasty = ROOT
culture_group = ROOT
}
has_opinion = { who = ROOT value = 75 }
reverse_has_opinion = { who = ROOT value = 75 }
is_subject = no
}
}

mean_time_to_happen = {
months = 500
}

option = {
name = dynastic_events.5.a
random_neighbor_country = {
limit = {
government = monarchy
has_heir = no
ruler_age = 16
NOT = {
ruler_age = 40
}
OR = {
AND = {
is_female = no
ROOT = {
is_female = yes
}
}
AND = {
is_female = yes
ROOT = {
is_female = no
}
}
}
OR = {
dynasty = ROOT
culture_group = ROOT
}
has_opinion = { who = ROOT value = 75 }
reverse_has_opinion = { who = ROOT value = 75 }
is_subject = no
}
country_event = {
id = dynastic_events.6
tooltip = dynastic_events.6.t
}
}
}

option = {
name = dynastic_events.5.b
add_legitimacy = 10
}
}

# Personal Union Offered
country_event = {
id = dynastic_events.6
title = dynastic_events.6.t
desc = dynastic_events.6.d
picture = DIPLOMACY_eventPicture

is_triggered_only = yes

option = {
name = dynastic_events.6.a
add_legitimacy = 20
FROM = {
set_country_flag = dyn_pu_accepted_flag
create_union = ROOT
country_event = {
id = dynastic_events.7
tooltip = dynastic_events.7.t
}
}
}

option = {
name = dynastic_events.6.b
FROM = {
set_country_flag = dyn_pu_refused_flag
add_opinion = {
modifier = opinion_spurned_pu
who = ROOT
}
add_casus_belli = {
target = ROOT
type = cb_insult
months = 12
}
country_event = {
id = dynastic_events.7
tooltip = dynastic_events.7.t
}
}
}
}

# A Political Marriage - Accepted or Not?
country_event = {
id = dynastic_events.7
title = dynastic_events.7.t
desc = dynastic_events.7.d
picture = DIPLOMACY_eventPicture

is_triggered_only = yes

option = {
name = dynastic_events.7.a
trigger = {
has_country_flag = dyn_pu_accepted_flag
}
add_legitimacy = 20
tooltip = {
create_union = FROM
}
}

option = {
name = dynastic_events.7.b
trigger = {
has_country_flag = dyn_pu_refused_flag
}
tooltip = {
add_opinion = {
modifier = opinion_spurned_pu
who = FROM
}
add_casus_belli = {
target = FROM
type = cb_insult
months = 12

Click to expand...

Both rulers must be between 16 and 40, the two nations involved must be neighbors, both nations must have no heirs, both rulers have to be of different sex and be either of the same dynasty or in the same culture group. Both nations need to have high enough opinion with each other. The MTTH of the start is 500 months. Portugal can get a UNION over Spain this way, Or Styria can get a Union over Austria.

OPTION D : You share a dynasty. They have a weak heir or a regency council FOR a weak heir.

You may claim the throne. You receive casus belli to start a war when you do a claim, and may force a union. If the king dies and the heir ascends, you will lose the casus belli and the claim to the throne once the heir makes a strong claim heir OR if a consort regency triggers. This seems buggy, but its the way it works.

solution: don't claim their throne until the heir is 15 to avoid losing claim to consort regency.

OPTION E : Succession war..

This is the most complex part of the game of thrones that eluded even the specialists of this forum for months. What comes next is my opinion of how it works, after input of many console testers who backed up or proved my assumptions wrong.

You, and several legible nations are interested in the succession of a target monarchy, with no heir. If the ruler there dies without an heir, you usually see a noble of your house seize their throne, if you have RM with that country and if you have highest development total of all their RM partners.

But if those other nations qualify to contest the outcome of this disputed succession in the heirless monarchy, then you get a succession war.

Military rating of nations or score of nations comes into play here. RULE OF THUMB: Among all possible aggressive claimants in a succession war (meaning your RM partners, the RM partners of the heirless nation, the nations that set YOU or the heirless nation as rival, and other nations with your dynasty): the nation with highest military rating/score gain and/or highest effective development (or a mix of the two combined in some obscure formulae) will get popup if they want to contest a succession aggressively in a succession war. Its not clear how aggressive claimant is chosen among all the possible nations unfortunately. But its likely a mix of the above.

Part 2 of this guide is a couple of posts below this or use link: https://forum.paradoxplaza.com/foru...unions-and-claim-throne.788829/#post-17713470