In Imperator, diplomacy involves the actions and treaties that countries conduct and sign with each other, ranging from a simple improvement of relations to demands for tribute and fully-fledged alliances and defensive pacts. The most important facet of diplomacy is a country's opinion of other countries, which significantly affects what diplomatic actions are possible and whether they look for cooperation and friendly relations or pursue a more aggressive policy. Most diplomatic actions and modifiers can be seen and accessed through the Diplomacy screen.
- 1 Opinion
- 2 Diplomatic relations
- 3 Diplomatic reputation
- 4 Diplomatic range
- 5 Diplomatic stance
- 6 Diplomatic actions
- 6.1 War Actions
- 6.2 Alliance Actions
- 6.3 Access Actions
- 6.4 Influence Actions
- 6.5 Covert Actions
- 6.6 Relation Actions
Every country has a specific opinion value of every other country ranging from -200 to +200, which represents how well that country sees the other country and is one of the most important factors in how they act towards each other. Countries with a high opinion of another country will be much more receptive to diplomatic and trade requests and will likely pursue a cooperative attitude, while countries with a low opinion will usually refuse requests or demands, break existing treaties, and regard the other country as a rival or enemy. Opinion values go only one way; a country's opinion of another country is not necessarily the same and often different from the second country's opinion of the first, and it is entirely possible that one first country is friendly to the other while the second is hostile.
A country's opinion of another country is determined by the sum of all opinion modifiers that the first country has towards the second. Some opinion modifiers are based on some persistent property of the two countries and their relationship, such as having the same religion, being in an alliance, or having a particular diplomatic stance; these modifiers have a fixed value and will remain as long as the source of the opinion modifier is still valid. Other opinion modifiers, usually given by events, missions, or other actions - particularly accumulating aggressive expansion - are temporary modifiers and have a specific yearly decay that reduces the effect of the modifier each year, until it reaches 0 and disappears. The Relations diplomatic actions category allows a country to directly influence another country's opinion of it, spending political influence or gold to improve relations or aggressive expansion to worsen them, though there is a limit to how much a country's opinion can be improved.
Most treaties, such as alliances, defensive leagues, and guarantees, as well as many types of subject states, take up one of a country's diplomatic relations slots. Every country has a cap on the amount of diplomatic relations it can have normally, with each relation over the limit giving a −10% political influence modifier. This diplomatic relations cap forces countries to carefully choose their allies and to some extent subjects to be as useful and reliable as possible, rather than simply accepting every treaty they can and creating a vast network of clients to easily overpower its rivals.
The most important modifiers for a country's diplomatic relations cap are listed below:
|Country rank||Great Power||+5|
|Inventions||Summitry ( Oratory Tech 9)||+1|
|Noble Envoys ( Oratory Tech 16)||+1|
|Foreign Network ( Oratory Tech 18)||+1|
|Diplomatic stance||Neutral Stance||+1|
|National ideas||Permanent Ambassadors ( Oratory idea)||+2|
|Laws||King of Kings (Monarchy law)||+2|
|Deities||Traphu (Bon deity)|
|Trapusa and Bahalika (Buddhist deity)|
|Heritages||Heritage of Kassandros (Macedon)||+2|
|Arvernian Heritage (Arvernia)||+1|
|Iberian Heritage (Iberia)||+1|
|Boeotian Heritage (Boeotia)||+1|
|Cyrenaican Heritage (Cyrenaica)||-1|
|Delphic Heritage (Delphi)||-1|
|Aetolian Heritage (Aetolia)||-1|
|Corinthian Heritage (Corinth)||-1|
|Bosporan Heritage (cultural)||-1|
|Religious State heritage (mission created)||-1|
A country's diplomatic reputation represents the effectiveness of its diplomats and affects how likely a country's diplomatic proposals will be accepted. Generally, every point of diplomatic reputation gives +1 point towards another country's acceptance of any diplomatic action. It is possible for diplomatic reputation to become negative, at which point it will make other countries less likely to accept diplomatic offers.
The main sources of diplomatic reputation are listed below:
|Inventions||Open Negotiations (Oratory Tech 4)||+2|
|Diplomatic actions||Supporting Rebellions Abroad||-5|
|Trade goods||Honey (capital bonus)||+3|
|Deities||Diktean Zeus (Cretan Hellenic deity)|
|Eacus (Iberic deity)|
|Blood of Lysimachus||+1|
|Heritages||Heritage of Antigonos (Antigonid Kingdom)||+2|
|Aeolian Heritage (Aeolia)||+2|
|Cnidusian Heritage (Knidos)||+2|
|Heritage of Kassandros (Macedon)||-2|
|Kalingan Heritage (Kalinga)||-2|
A country can only use most diplomatic actions on other states within diplomatic range, except for ending or declaring wars and asking for or canceling military access. Another country is considered to be within diplomatic range if the distance from the current country's capital to its capital is within the current country's diplomatic range value. A country's diplomatic range is significantly increased by inventions and country rank; this means that it is possible for a larger power to initiate diplomacy with a smaller, somewhat distant country even if the converse is not possible. In addition, all neighbouring countries are considered to be within diplomatic range, regardless of the distance to their capital.
Each country chooses a default diplomatic stance from five choices. Changing stance costs a base of 30 Political Influence, increasing by +10% for each previous stance change done by the current ruler.
These are as follow:
Diplomatic actions are the primary way that two countries interact with each other, allowing a country to negotiate various agreements, make demands, improve relations, and more. Many diplomatic actions have certain restrictions, such as requiring a certain country rank or opinion threshold; most actions also require that the target country be within diplomatic range, and cannot be done by or to subject states. After taking an action, the current country will be unable to take any more diplomatic actions against the same country for the next 30 days.
If the government type is a republic, the senate will vote on all diplomatic actions. As with all such actions, the Senate must have at least 40 approval to take most diplomatic actions, and pushing it through will cost scaling tyranny unless the country has at least 60 Senate approval.
- Main article: Warfare
Declares war on another state, hidden if the country is already at war with this faction (even if only as a secondary participant). A casus belli (CB - Reason for War) and wargoal to be used in this war must be chosen, which will determine the goal of the war to get ticking warscore. War may be declared without a valid CB but this will incur a large penalty to aggressive expansion, stability, and war exhaustion. Wars cannot be declared if the country has less than 30 stability.
Sue for Peace
Open a window to choose a negotiated end to wartime hostilities. Only available if at least one of the parties involved is the warleader of their side, and secondary participants cannot sue for peace for the first 36 months of a war unless they are completely occupied. Subjects can never sign a separate peace.
Demand Military Access
Sends a demand for another country to allow through their country. If refused, the current country will immediately declare war with the Gain Military Access wargoal, with the attacker unable to call in allies. This is a special type of war where no demands can be made except that the victor will always gain through the losing party's territory for the duration of the truce.
Ransoms a character that is imprisoned by the other country. The price required depends on the other country's opinion of the current country and the imprisoned character's attributes, with a significant emphasis on martial skill. Most commonly used for commanders that have been captured after losing a battle.
- Main article: Treaties
Creates an alliance between two states, where the two countries agree to aid each other in defensive wars and can be called to arms in offensive wars. Allies get +50 opinion with each other. Cannot be done if either side is a great power.
Creates a guarantee of protection from the current country toward another state of lower rank, where the guarantor agrees to aid the other country if is attacked by another power. The country being guaranteed gets +10 opinion towards their guarantor, and the guarantor gets +5 opinion towards the country being protected. Restricted to Regional powers or above.
Invite to/Join/Leave Defensive League
Create a new defensive league or join, invite to, or leave an existing one, where all members of the pact agree to aid the others if any of them are attacked. Only the leader of the defensive league can invite other countries to join. Members of a defensive pact get +25 opinion towards all members. Restricted to City States and Local Powers.
Ask/Cancel Military Access
Ask another country for military access, which lets a country freely move its armies through another state's territories and dock its navies in the other state's ports. A country that has military access through another country gets +10 opinion of that country. Unlike most actions, asking for or cancelling military access does not require the target country to be within diplomatic range.
Offer/Revoke Military Access
- See also: Subject nations
Cancel Subject Status
Begin the process of annexing a subject state into an integral part of the country. Can only be used on certain types of subjects (e.g. feudatories, client states, satrapies) and requires that the subject have at least +190 opinion of the overlord and that the subject has been under its overlord for at least 10 years.
Integration can be aborted at any time, but all progress will be lost.
Demand Subject Transfer
Can be used on disloyal subjects of another country to have them peacefully transfer their allegiance to the current country. Requires that the subject has at least +80 opinion of the potential new overlord.
Demand Subject Status
Send an offer for the target country to peacefully become a subject of the current country, requiring the other country to have at least +100 opinion of the current country. Different actions are available for all subject types that are possible between the potential subject and overlord. Countries are typically hesitant to accept subject status unless the current country is much stronger than the target.
Intervene in War
Joins the side of the target country in one of their wars, requiring that the target country has at least 100 opinion of the current country and that the current country is at peace. Can only be done by Great powers, or Rome if it has adopted the Power Diplomacy invention (requires Oratory Advances 5).
Demands that another country cede a single territory that the current country has a on, starting a for that territory if they refuse. Restricted to Regional Powers or above.
Allows a country to sell a single territory to another country in return for gold. In particular, can be used to grant territories to subject states (i.e. by selling territories for free). There are no restrictions on what territories can be sold - even if they are not adjacent to any of the potential buyer's territory - though the buyer is unlikely to accept unless it is neighbouring or otherwise interesting (e.g. same dominant culture or has a claim).
Support Rebels/Abort Rebel Support
Supports rebels and stirs discontent in another country, giving -8% Unintegrated Culture Group Happiness to the target and +0.02 Aggressive Expansion Change and -5 Diplomatic Reputation to the current country while it lasts. Starting to support rebels also gives +2 aggressive expansion. The target will get a Show Superiority casus belli against the current country, and the current country will join any rebellions that happen against the target. Cannot be used if the current country is at war or has a truce with the target, and is restricted to Major Powers and above.
Fabricate/Cancel Fabricate Claims
- Main article: Claim
Starts the process of fabricating a claim on a specific province, which gives a casus belli and war goal. Costs a base of 20 political power, and can only be done on provinces within control range (i.e. neighbouring the current country or has a nearby coast). Only one claim can be fabricated on a country at a time.
Improve Opinion/Cancel Improve Opinion
Start the process of passively improve another state's opinion of the current country, which costs 10 political influence to start. Improving relations has a base cap of +100 for subjects and +50 for all other countries, modified by the Improve Opinion Maximum modifier. Opinion is improved by 1% of the cap each month, and decays by 1 each month once the action is no longer active. The opinion improvement process can be cancelled at any time, and will be automatically cancelled once the modifier reaches its cap.
The most important modifiers for a country's improve opinion maximum are listed below:
|Type||Modifier||Improve Opinion Maximum|
|Inventions||Proxenoi ( Oratory Tech 0)||+20%|
|National Seal ( Oratory Tech 3)||+20%|
|Permanent Ambassadors ( Oratory Tech 8)||+20%|
|Hereditary Ambassadorship ( Oratory Tech 13)||+20%|
|National ideas||Hospitium ( Oratory idea)||+33%|
|Heritages||Tarentine Heritage (Tarentum)||+10%|
|Iceni Heritage (Icenia)||-10%|
|Montane Heritage (group)||-10%|
Insult another state, giving -50 opinion with a yearly decay of 1 and gaining 1 aggressive expansion. Insults can be stacked to decrease opinion arbitrarily low, and the target country gets a limited duration Show Superiority Casus Belli.
Send 2.4 times the target country's monthly income for the target to gain +25 opinion of the current country, with a yearly decay of 1. The maximum total opinion boost from gifts is capped at +25; subsequent gifts will set the value of the modifier back to +25, but cannot be used to stack the opinion bonus higher.