- This article is about the ingame concept of countries and their associated mechanics. For a list of all countries in the game, see Countries.
A state, or a country, is an autonomous political structure comprising a community of people organized under some form of government, and is the main playable focus of Imperator: Rome. A state has a court of characters, including a 
ruler; has control over some amount of territory and the population that lives there (except for 
Migrant Hordes); a government form and laws that define many aspects of how the country is run; a primary 
culture and state 
religion that will affect the happiness and civic rights of its pops; and various accumulated values such as 
gold, 
manpower, 
political influence, and 
stability that represent the resources available to the country and the current state of its well-being. Countries can interact with each other through diplomacy, trade, and 
war, and a state may be independent or be a 
subject of a stronger suzerain. The world is populated by hundreds of countries at the start of the game, from minor tribes and city states to the great empires of the east, many of which will likely soon disappear but some who may rise to form one of the great empires that the era was known for.
Government
- 主条目：Government
One of the main defining features of a country is its 
government type, which can be classified into one of three more general government forms - Republic, Monarchy or Tribal.
Different government types have different modifiers, bonuses, and National Idea slots, and it can be useful to switch to one that better synergizes with the current strategy and playstyle. Changing between government types is generally done by 
decision and the requirements can generally be seen at any time. These requirements may include a minimum stability level, certain laws (or not having certain laws), a minimum 
civilization value in the 
capital territory, a specific 
technology level, and more, and will almost always cost stability. Certain 
mission trees, such as the 
Carthaginian mission tree Aftermath of the Revolution, may also allow for changing government type even when if the country does not meet the normal requirements.
The government form defines the method of succession, the available 
laws, and the makeup of the 
offices, which give political influence and various bonuses according to the character's attributes and 
loyalty. Each government form also has different mechanics that a player must deal with - republics must seek the 
approval of the Senate for nearly every major action, monarchies must watch their 
legitimacy and deal with angry 
pretenders, and tribes must appease their powerful 
clan chiefs and decide on the direction of 
centralization. Government offices also provide political influence depending upon the holder's loyalty. Changing the government form is usually harder than changing government type; reforming from a Tribal government to a Republic or Monarchy involves going through the Tribal Reform mission tree, changing from a Republic to a Monarchy requires high 
tyranny and the declaration of a Dictatorship through one of the 
Line of Succession inventions, and changing from a Monarchy to a Republic is not generally possible outside of a few special events or missions (such as the 
Syracusan mission tree Death to Tyrants).
Ruler
- 主条目：Ruler
Each state is headed by a ruler, prominently visible on the main tab of the government panel, and their traits, attributes, and relationships have a significant effect on character loyalty and many important country modifiers from 
national commerce income to 
army morale recovery to File:Stability monthly change.png monthly stability change. Rulers with high attributes can be a considerable boon to their country, significantly strengthening the state and allowing the nation to punch well above its weight, while corrupt, low attribute rulers can inflict major penalties that a state must struggle through. A ruler may be supported by a co-ruler or consort, who contribute any of their four main attributes if they are higher than those of the ruler, but may also have effects on political influence generation if disloyal and contribute to modifiers for ruler 
popularity and 
corruption. Succession varies widely depending on the country's government form, ranging between dynastic inheritance in a monarchy, Senatorial election in republics, and rotation between Clan Chiefs in tribes; the length of office may vary widely as well, from the shortest possible 2-year term to lifetime rule typical of more autocratic systems.
Culture
 |
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Every country begins the game with a predefined primary culture, which can be seen at the top right corner of the 
National Overview screen. Outside of a few special events and decisions, such as startup events for 
本都的赫拉克利亚 and 
埃及, the 请检查模板名和国家代码：{{Countries|flag/core|Parthia (Formable)}} Parthia formation decision, and events during the Yuezhi migrations, the primary culture generally cannot be changed except for during a barbarian takeover.
Pops of the primary culture are typically the happiest and most satisfied pops in the realm, and are fixed to the 
civic right. Most often the culture of the state population is more diverse, but pop culture can be gradually changed to match that of the state during the playthrough via assimilation, as pops of a different culture and especially culture group have a significant happiness malus that can become very difficult to manage if stability begins to drop. Assimilation is also slowed if the dominant province culture and/or religion is not the same as that of the state, all of which makes the conquest of wrong culture (especially wrong culture group) and wrong religion areas significantly more difficult, especially in the early game. Outside of events pops will always assimilate and convert to the primary culture. As an alternative to assimilation, cultures can be 
integrated to be given the same rights as the primary culture, at the expense of the happiness of already integrated cultures.
The primary culture also has an effect on diplomacy. States of a different culture (in the same culture group) get a 
-10 opinion malus, while those in a different culture group get a -20 opinion malus. The subject types available also depend on primary culture; another state can only be made a feudatory if it is in the same culture group as its new overlord, and satrapies can only be made of states with Persian military traditions, which consist mostly of countries in the Iranian, Caucasian, Anatolian, Scythian, Bactrian, and Aramaic culture groups.
The state's 
Military Tradition tree, which determines the unit abilities and bonuses that can be accrued over the game by spending 
military experience, is fixed at the start of the game based on the primary culture/culture group (with a few exceptions) and cannot be changed except for through a few special events (such as the 本都的赫拉克利亚 startup event).
Religion
Every country starts with a predefined state religion, which can be viewed just above the pantheon deities in the File:Menu religion.png Religion tab. Every religion has bonuses that are applied to the entire country, and also determines the base deities that are always available regardless of the population or holy sites of the country. State religion also has a small effect on diplomacy—countries of the same religion get a +10 opinion bonus with each other. There is no malus for having a different state religion.
There is no default happiness bonus or penalty for pop religion, but pops will receive a 
+4% happiness bonus for each deity in the state pantheon that matches their religion, making it useful for polytheistic states to take on pantheon gods of religions that are widespread inside their country - though spreading out the deity happiness bonus between deities of different religions means a smaller happiness modifier for each individual religion. The happiness of state religion pops specifically is also be increased with the 
state religion happiness modifier, which is given by various omens and deities, inventions, laws, heritages, and more.
Additionally, the percentage of pops following the state religion determines the nation's 
Religious Unity value, which is the main component of 
omen power.
State Conversion
The state religion can be changed by decision if there is at least 1 character of the new religion in the country, and either 50% of the non-slave pops in the capital, or at least 20% of all the pops of the country and at least one 
pantheon deity, follow the new religion the country intends to convert to. Switching religions can only be done once every 10 years and costs 200 political influence and 30 stability, also giving a temporary drop of −15 Loyalty for all characters that are followers of the old faith.
Heritage
- 主条目：Heritage
Each nation also has a set heritage, usually with two bonuses and one malus reflecting its culture, history, or ambitions. Some countries have their own unique heritages, while others have a more generic group heritage depending on its culture or starting position. A country's heritage cannot be changed, even when forming a new nation, outside of a few rare events, and its modifiers are applied to the country for the whole game.
Accumulated points
Wealth
- 主条目：Economy
The nation's Treasury stores all of its currently accumulated wealth, or gold. The nation's income is calculated monthly and comes from 
tax collection, 
domestic commerce and trade route income, and 
subject tributes. Many events can also give gold into the treasury, often scaled by the nation's current income.
Monthly expenses include 
army and fleet maintenance, tributes to an overlord, 
fort maintenance and 
character wages. Wealth is also spent on building costs, founding cities/metropolises, recruiting 
legions and 
mercenaries, certain character interactions, 
slave resettlement between territories, and much more, particularly events and missions. It is sometimes possible for a state to spend more money than it currently has in its treasury, which will put it into 
deficit with impacts on stability and political influence generation. If a state runs into deficit, events will trigger that grant gold in exchange for a temporary malus, which generally ensure that countries never stay in deficit for too long.
Manpower
Manpower represents a pool of ready-to-fight people who are drawn from 
citizen, 
freeman, and 
tribesman pops inhabiting a state. Manpower is used when recruiting new legion cohorts and replenishing 
attrition or combat losses; if manpower becomes low, a nation can become vulnerable to attack. Each point of manpower provides one soldier for a newly recruited or reinforcing cohort; if a country runs out of manpower, they will no longer be able to recruit any more cohorts or reinforce their armies until it replenishes (note that this does not include raising 
levies, but does include reinforcing them).
The base yearly manpower production of each country is determined by its national manpower, which is a base of +125 for most countries with an additional +500 for migrant hordes. This base manpower production is then increased by the output of the citizen, freeman, and tribesman pops in the country. Each citizen produces a base of +2 manpower, each freemen a base of +4, and each tribesmen a base of +3 manpower per pop per year, which is then scaled to the pop's happiness. After applying 
all population output modifiers, the amount of manpower that a pop produces is further increased country-wide by the File:Global manpower modifier.png national manpower and locally by the File:Global manpower modifier.png local manpower modifiers, which are given by several trade good bonuses (e.g. 
wood) and from the 
Barracks and 
Training Camp buildings. Note that File:Global manpower modifier.png global manpower modifiers are only applied to manpower production from pops, not from the base manpower from the national manpower modifier, which is a significant difference for less populous countries. Like all other pop outputs, citizen, freeman, and tribesman happiness and output modifiers will also increase the manpower that they produce.
This gives a final yearly manpower formula of:
- [math]\displaystyle{ \text{Yearly Manpower}=\text{National Manpower} + \sum_\text{Territories} \sum_\text{Pops} \left(\text{Base Pop Manpower Production} \cdot \frac{\text{Pop Happiness}}{100%} \cdot \left(1 + \frac{\text{Pop Output Modifiers}}{100%}\right) \cdot \left(1 + \frac{\text{Manpower Modifiers}}{100%}\right)\right) }[/math]
A country's maximum manpower is then 11 times the country's total yearly manpower production (including the base national manpower, which gives a base manpower pool of 1375 for each nation). If the current manpower pool is below the cap, it will recover by a base of 1/132nd each month, so that refilling the pool takes 11 years. For each territory, the part of the manpower gain that comes from pops (i.e. 1/12th of the local yearly manpower production) is modified by the national 
manpower recovery speed modifier before being listed on the territory interface as the monthly manpower gain, and this part of the country's manpower production is summed up across all territories as well as with the monthly manpower production from the base national manpower to give the final manpower gained from pops. Manpower recovery is also given as the tribute of certain subject types, such as feudatories and tribal vassals (note that while the tribute will appear in the total monthly manpower gain for the overlord, it is not explicitly shown in the manpower tooltip for the subject, though the manpower will still be deducted at the beginning of each month regardless).
This can be expressed as the following formula:
- [math]\displaystyle{ \text{National Monthly Manpower Gain}=\frac{\text{National Manpower} \cdot 11}{132} + \frac{\text{Yearly Manpower from Pops} \cdot 11}{132} \cdot \left(1 + \frac{\text{Manpower Recovery Speed}}{100%}\right) + \text{Monthly Manpower from Tribute} }[/math]
Political Influence
Political Influence represents the state's accumulated political capital and is used to perform many actions directly relating to the government or administration, such as selecting national ideas, implementing laws, increasing stability, fabricating 
claims, founding 
cities, making 
province investments, building 
wonders, and more.
It is an abstract currency generated by loyal members of your government over time, who are chosen as office holders. The total value accrued each month is determined by each character's Loyalty, therefore, it may fluctuate consistently over the year. Each government office provides up to +0.25 per month, scaling by the holder's loyalty up to 100. Many inventions increase political influence gain on top of that, while ruler corruption and consort or co-ruler disloyalty can significantly reduce it.
Military Experience
Military Experience is a countrywide value that measures the degree of practical military knowledge and expertise the state has built up. This currency is primarily used to embrace military traditions, at a cost of 80 military experience for each tradition.
Military Experience increases by a base of +0.30 per month, plus an additional +0.006 for every point of average cohort experience across all armies (for a base maximum of +0.90). Various other modifiers such as 
war exhaustion, being in a defensive war, and certain deities, religions, and laws give an additional positive modifier to military experience gain, while mercenary reliance reduces the rate at which military experience is generated. Other than training up cohorts by fighting battles in war, a country can also use the 
Drill Army legion ability during peacetime to build up cohort experience in exchange for increased 
legion maintenance cost and 
loyalty gain chance.
While levies cannot be drilled and so cannot reach particularly high military experience levels, disbanding a levy that has been raised for at least 8 months will grant 0.015 military experience for each point of cohort experience, which can be very substantial for larger countries that have a significant 
starting experience modifier. There are also a number of events and mission tasks that give military experience, as well as the 
apotheosis effect of certain deities when replaced with a deified ruler.
Every point of military experience stored gives a 
+0.05% army morale bonus to the country's cohorts, with a maximum bonus of +10% when the stored military experience reaches its cap at 200 points. The bonus is reduced once the military experience is used on military traditions, mission requirements or in events.
Research
Research Points represent the progression of techniques, discoveries, and general technology over the course of time. They are produced by nobles and citizens inhabiting a state, and the yearly research output as a proportion of the number of integrated culture pops in the country determines the rate of progress in technological advances. It is generally recommended that at least 1/3 of a state's integrated culture population is made up of nobles and citizens in order to achieve at least 100% research efficiency, but how much is actually needed will vary widely depend on the proportion of nobles to citizens, as nobles produce much more research per pop, as well as the amount of research produced by unintegrated cultures (who do not count against the denominator of research efficiency). Research point production can be increased directly many modifiers, such as the 
library city building and trade goods bonuses (cloth, earthenware, glass and papyrus), and is also sensitive to noble and citizen happiness and output modifiers. Research point production can be tracked on the technology panel.
Research points are automatically spent towards advancing the four fields of technology: martial, civil, oratory and religious, modified by researcher skill. Each new advance in a field grants a small bonus for each level and grants an innovation, which can then be used to purchase inventions that give a wide variety of other useful modifiers.
Stability
Stability represents the trust that the characters and population of your country has in your government, and its general ability to withstand threats and discontent from within. Stability runs from 0 to 100, with a base value of 50 that the stability value will naturally decay to. Positive (above 50) has many economic benefits, increasing 
population growth, population happiness, research points, and legitimacy. Negative stability (below 50) will instead decrease population happiness and legitimacy (in monarchies), making it more likely that a revolt will break out if stability is not quickly raised.
Stability is decreased by certain diplomatic or political actions, such as breaking 
truces, changing laws or government form, swapping pantheon deities, or granting many cultural privileges. It is also spent by migratory tribes to start 
migrations. The primary method of increasing stability more quickly is to spend political influence to make 
Divine Sacrifices in the Religion view, which will increase the monthly stability change. Certain omens, traits, and laws also increase monthly stability change, as does ruler zeal, and many Queued Events also offer semi-reliable immediate stability boosts, usually at the cost of spending or forgoing a bonus in some other currency (especially gold and political influence). High 
aggressive expansion, low senate approval (in republics), being in deficit, and 
integrating cultures are some of the main factors that will decrease stability over time, and should be watched carefully.
A nation is considered disorganized if stability is below 20, which will prevent the country from reassigning government offices or declaring wars.
Generally speaking higher stability is always better, though because decay increases as stability gets further away from 50, it is usually not worth it to intentionally try to keep stability very high. Low stability should always be a cause for concern unless your nation is very well managed, as prolonged instability will lead to widespread unhappiness and 
unrest, and eventually rebellions.
Every point of stability above 50 has the following effects:
- +0.002% National Population Growth
- +0.2% Population Happiness
+0.003 Monthly Legitimacy- +0.5% Research Points
Every point of stability below 50 has the following effects:
- -1% Population Happiness
- -0.01 Monthly Legitimacy
- -0.01% Monthly Stability Decay
Note that since stability decays towards 50, the stability decay reduction from low stability means that the base change of stability up towards 50 is more slow than the decay down towards 50 from high stability.
Aggressive Expansion
Aggressive Expansion (AE) represents the resentment that other states and pops in your empire have against conquests and other aggressive actions you take. The primary effect of Aggressive Expansion is to decrease realm stability and lower the loyalty of all subject states, which can have a significant impact on population happiness and unrest at higher levels and raise the risk of rebellions if not handled properly. Higher Aggressive Expansion also significantly decreases the opinion of nearby states (though allies have a much reduced opinion malus) and makes it more likely that the nation is viewed as a threat, making it more difficult to conduct diplomacy and encouraging other states to form 
alliances or 
defensive leagues against the expanding country. Very high Aggressive Expansion will have additional effects on integrated culture pops as well as reducing political influence generation. Aggressive Expansion has a base value of 0, where it has no effects, and can become arbitrarily high, but cannot become negative.
Each point of Aggressive Expansion has the following modifiers:
-0.02 Claim Fabrication Speed
-0.25 Loyalty of Subject States- -0.0075 Monthly Stability Change
Each point of Aggressive Expansion beyond 50 also has the following effects, in addition to the ones above:
-0.30% Integrated Culture Happiness- -2% Aggressive Expansion Impact
- -0.10% Monthly Political Influence
+1.5% Divine Sacrifice Cost
Aggressive Expansion is primarily accrued through conquering new territories or forcing vassalization during a war. Several diplomatic actions, character interactions, and unit abilities also increase Aggressive Expansion.
 gain
|
Type | |
|---|---|---|
| +25 |
| |
| +20 |
| |
| +15 |
| |
| +10 |
| |
| +7 |
| |
| +5 |
| |
| +2 |
| |
| +1 |
| |
| +0.75 |
| |
| +0.5 |
| |
| -5 |
| |
| -10 |
|
The base 
Aggressive Expansion Decay is -0.20% of current Aggressive Expansion per month, which is be increased by another -0.20% with the 
Appeasing Diplomatic Stance, +0.03% from every point of positive 
diplomatic reputation, and another -0.20% if the ruler has the 
Righteous trait; however, this decay is active only if your country is not currently on the side of the aggressor in a war. There are also several sources of flat monthly 
Aggressive Expansion Change that is active at all times, including Oratory inventions, government offices, and various deities. All static sources of monthly Aggressive Expansion Change are listed below:
|
|
Type | |
|---|---|---|
| +0.020 |
| |
| -0.004 |
| |
| -0.010 |
| |
| -0.015 |
| |
| -0.020 |
| |
| -0.025 |
| |
| -0.03125 |
| |
| -0.040 |
| |
| -0.050 |
| |
| -0.0625 |
|
Aggressive Expansion Impact modifies how much aggressive expansion is accrued from conquering land and vassalizing other states after a war, primarily decreasing the AE cost of conquest. Sources of Aggressive Expansion Impact include Oratory inventions, Laws, ruler traits, heritages, mission/event modifiers, and high aggressive expansion; the last in particular means that at some point above 50 you will accrue very little additional Aggressive Expansion for any further conquests, effectively providing a soft cap to the modifier. The effects of Aggressive Expansion Impact are capped at -95.00%, corresponding to an absolute minimum of +0.05 aggressive expansion per territory annexed or vassalized. Static sources of Aggressive Expansion Impact are listed below:
|
|
Type | |
|---|---|---|
| +33.00% |
| |
| +15.00% |
| |
| +10.00% |
| |
| -2.00% | per point of Aggressive Expansion above 50
| |
| -2.50% |
| |
| -5.00% | ||
| -6.25% |
| |
| -10.00% |
| |
| -20.00% |
| |
| -50.00% |
|
The impact of Aggressive Expansion is felt most in the early game, when diplomacy is most important and the lack of Aggression Expansion Impact means that taking even a few provinces can rack up a significant amount of Aggressive Expansion. Spending political influence on Divine Sacrifices as well as assigning governor armies to suppress unrest and handle 
province loyalty, particularly in already less happy unintegrated culture group provinces, may be necessary to deal with and counteract the loss of stability, while judicious use of Improving Relations can help prevent the diplomatic situation from getting out of hand. An expansionist empire should focus on sources of Aggressive Expansion Change and Impact, while general happiness and stability modifiers - as well as focusing on stability when taking events from the Event queue - will help deal with the stability loss from aggressive expansion. In the later game, when the player has built up a large empire that can easily stand against its neighbours, accumulated many of the AE Change and Impact modifiers, and either accrued enough happiness modifiers or have sufficient garrison army capacity to handle the loss of stability even at relatively high AE values, an empire can take advantage of the Aggressive Expansion Impact for having higher than 50 AE to be able to conquer large amounts of territory at little to no additional aggressive expansion penalty, at which point the main hindrance will be keeping stability above 30 in order to be able to declare wars (assuming the country is stable enough to survive at low stability).
Tyranny
Tyranny represents the level of oppression in your country and produces resentment against the government by characters and primary culture pops, but also increases the willingness of pops and factions to accede to the government's demands and centralization of power. The level of Tyranny must be carefully managed, particularly in the early game, in order to avoid large reductions in character loyalty that can ensue in 
civil war, but in the later game when inventions and growth in power make characters and pops easier to deal with the aggressive expansion change and 
national slave output can become quite useful. The base Tyranny values range from the base value of 0, where it has no effects, to 100, and cannot be negative.
Each point of Tyranny gives the following modifiers:
-0.004 Aggressive Expansion Change- +0.20% Cohort Loyalty Gain Chance
-0.12% Threshold for Civil War
-0.12 Loyalty of Characters- +0.50% National Slave Output
-1.00% Imprison Cost- -1.00% Execute Cost
Tyranny is primarily increased by various character actions, such as imprisoning, executing, and imposing sanctions on various characters, as well as 
invoking devotio to reduce war exhaustion and when overriding the will of the Senate in Republics when doing character interactions, changing laws, or conducting diplomacy. There are also many events, particularly those relating to characters and their interactions, that can raise or lower the country's tyranny level. The actions and interactions that cost or change the national Tyranny value are listed below by their base cost, which can be changed by various interaction-specific modifiers:
| Tyranny gain
|
Type | |
|---|---|---|
| +30 |
| |
| +10 |
| |
| +7 |
| |
| +5 |
| |
| +4 |
| |
| +3 |
| |
| +2 |
| |
| +1 |
| |
| +0.67 |
| |
| +0.5 |
| |
| +0.01 |
| |
| -1 |
| |
| -5 |
|
Tyranny is primarily lost through 
Monthly Tyranny change, which has a base reduction of -0.02 Tyranny per month. This can be increased and changed by different modifiers, such as certain oratory inventions, various deity and omen bonuses, ruler attributes and traits, and more; sources of monthly tyranny change are listed below:
| Type | Modifier | Monthly Tyranny
|
|
|---|---|---|---|
| Base | Base | -0.02 | |
| Government | Aristocratic Monarchy Government Bonus
|
-0.05 | |
| Strengthening Legitimacy
|
+0.025 per instance | ||
| Senate Approval
|
-0.003 per point above 50 | ||
| National ideas |  Divine Mandate
|
-0.04 | |
| Inventions | Official Orators ( Oratory Invention)
|
-0.01 | |
| Symbolic Victory ( Oratory Invention)
|
-0.02 | ||
| Hierarchy of Responsibility ( Oratory Invention)
|
-0.02 | ||
| Seeded Acclamation ( Oratory Invention)
|
-0.01 | ||
| Adventus ( Oratory Invention)
|
-0.01 | ||
| Chironomia ( Oratory Invention)
|
-0.01 | ||
Cursus Publicus (Italic  Civic Invention)
|
-0.01 | ||
| Rewrite the Constitution (Republic Oratory Invention)
|
+0.02 | ||
| Trade |  Marble Capital Surplus Bonus
|
-0.015 | |
| Laws | Assembly of Citizens (Republic)
|
-0.02 | |
| Curiate Assembly (Roman Republic)
|
-0.02 | ||
| Council Legal Authority (Tribal)
|
-0.05 | ||
| Deities |  Men (Cybelene deity)
|
||
| Vishwanath (Hindu deity)
| |||
| Betatun (Iberic deity)
| |||
| Omens | Kopala Omen (Armazic deity)
|
| |
| Ba'al Qarnaim Omen ( Carthaginian Canaanite deity)
| |||
| Lenus Omen (Treverian Druidic deity)
| |||
| Leto Omen (Hellenic deity)
| |||
| Diktean Zeus Omen (Cretan Hellenic deity)
| |||
| Nortia Omen (Etruscan Hellenic deity)
| |||
| Wisdom of Bhadrabahu Omen (Jain deity)
| |||
| Caleb and Joshua Omen (Jewish deity)
| |||
| Banebdjed Omen (Kemetic deity)
| |||
| Tir Omen (Armenian Khaldic deity)
| |||
| Deivas Omen (Matrist deity)
| |||
| Derzelas Omen (Zalmoxian deity)
| |||
| Ruler |  Charisma
|
-0.01 per point | |
| Popularity
|
-0.001 per point above 50 | ||
 Merciful (Ruler Trait)
|
| ||
 Forgiving (Ruler Trait)
| |||
 Trusting (Ruler Trait)
| |||
 Cruel (Ruler Trait)
|
+0.02 | ||
| Apotheosis
|
+0.01 per Deified Ruler in Pantheon | ||
| Heritage |  Athenian Heritage (Athens)
|
-0.02 |
While nominally a negative modifier, tyranny is generally not particularly problematic at lower levels and it is not very important to keep it low unless the nation is already experiencing issues with character loyalty. The invoke devotio action in particular can be used to essentially gain in return for reducing war exhaustion, effectively converting population unhappiness (and corresponding unrest) into character loyalty, which is generally easier to deal with, especially if the country does not have much other tyranny to begin with.
It is worth noting that since Tyranny decay does not scale according to its current value and there are no easy ways to quickly lower it, high Tyranny can be problematic if the state is not prepared, especially if the ruler has low Charisma and so the state has low base tyranny decay - if this becomes the case, the loyalty of powerful characters needs to be assured at all costs, or the country could easily spiral into civil war. The significant character loyalty and civil war threshold maluses together can be dangerous if not kept under control by other means, as even a single disloyal family head might be enough to trigger a civil war. Republics in particular need to pay close attention to tyranny levels, as tyranny reduces 
Democrat support which can be highly problematic if they make up a significant portion of the Senate - especially if that in turn lowers overall senate support to the point where taking any actions accrues even more tyranny. On the flip side, tyranny pleases the 
Oligarchs, making high tyranny an option to consider if they make up a significant portion of the Senate.
In the later game, if and when the player has accumulated enough loyalty bonuses to handle the penalties, high Tyranny is much more useful and players can take full advantage of its bonuses, particularly its effects on aggressive expansion change. In conjunction with further reductions from other sources and growing Aggressive Expansion Impact bonuses, a country with high Tyranny can handle much larger conquests and aggressive expansion values in the lategame as opposed to what is feasible early on. The National Slave Output can also be quite useful once all the loyalty problems can be properly dealt with, making for a powerful tyrannical empire.
War Exhaustion
War exhaustion represents anger and discontent in the general population from the human and economic cost of war. Raising a region's levies costs 0.5 war exhaustion, and keeping levies raised for more than 6 months will give an additional monthly war exhaustion penalty that increases the longer the levy is raised. Casualties, blockades, and enemy occupation can also contribute significantly to increasing a country's war exhaustion.
The effects of war exhaustion can be significant, decreasing happiness of all pops and impacting ruler popularity, but also increasing military experience gain and so can some amount of war exhaustion can be useful if the country is sufficiently stable. High War Exhaustion will increase the AI's willingness to sign a more favourable peace, and conversely may force a player to sign a less favourable peace treaty rather than let their nation be consumed by unrest. War Exhaustion ticks down slowly while at peace and based on the ruler's current zeal, which can be increased through various omens, laws, and ideas. If War Exhaustion becomes too high, the Invoke Devotio action in the religion panel can be taken to increase War Exhaustion decay at the cost of Tyranny. War exhaustion generally has a value between 0 and 20, but can rise to 30 for the attacker in an offensive war.
Each point of war exhaustion has the following effects:
- -0.5% Population Happiness
- -0.01 Monthly Ruler Popularity Gain
- +2.5% Monthly Military Experience
State rank
A country's rank is a measure of how large and influential a particular state is, based largely on the number of territories that it owns. Country rank is one of the primary determinants of the number of major families/clan chiefs, 
diplomatic range, and 
integration speed as well as significantly impacting political influence generation, integrated culture happiness, and 
warscore cost but higher ranked nations are also more vulnerable to civil war and rebellions as they have lower 
office loyalty as well as a province loyalty malus and a lower civil war threshold.
| Rank |  Number of Territories*
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No. of families |
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Other modifiers |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 Migrant Horde
|
0 | - | - | - | - | - | - | - | - | - | - | 3 | 3 | - | - | - | - |
|
 City State
|
1 | - | -15% | +0.05 | +2 | - | - | - | - | +1 | -15% | 3 | 3 | - | - | +2.5% | - |
|
 Local Power
|
2-24 | - | -10% | +0.10 | +1 | - | +4% | +10% | - | +1 | -10% | 3 | 3 | - | - | +5% | - |
|
 Regional Power
|
25-99 | +1 | -5% | +0.15 | +1 | +5% | +8% | +50% | -5% | +2 | - | 4 | 4 | -3% | - | +7.5% | - |
|
 Major Power
|
100-499 | +2 | - | +0.20 | +2 | +10% | +12% | +125% | -10% | +3 | - | 4 | 5 | -5% | -2.5 | +10% | -10% |
|
 Great Power
|
500+ | +2 | - | +0.25 | +2 | +15% | +16% | +225% | -15% | +3 | - | 5 | 5 | -8% | -5 | +15% | -30% |
|
* Subject nations are additionally capped at 
local power status, regardless of how big they get.
Country rank is also particularly important for diplomacy, as certain diplomatic actions are available only to countries of a certain rank.
| Rank | Defensive League
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Alliance
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 Guarantee
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 Threaten War
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 Support Rebels
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 Enforce Peace
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Intervene in War
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|---|---|---|---|---|---|---|---|
| Migrant Horde
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| City State
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| Local Power
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| Regional Power
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| Major Power
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| Great Power
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Maximum civilization value
Every country has a base country civilization level, visible on the 
Nation Overview panel, that determines the baseline maximum possible civilization level of every territory that the country owns. This value can be increased by a number of different modifiers, such as country's government type, positive centralization for tribes (up to +10% at 100), Oratory Advances (+0.5% per level), the national idea 
State Religion (+5%), the 
gemstones and 
glass capital surplus bonuses (+5% each), and various other more specific modifiers.
Note that the country civilization level is only the baseline maximum civilization; individual province and territory modifiers such as buildings, treasures, terrain type, special modifiers, and capital bonuses awarded when creating a formable nation can push the maximum civilization value of any individual territory higher than the country civilization value, often much higher for large, built up cities.
参考资料