Diplomacy System#

Diplomacy System

Diplomatic Relationship Types#

Relationship	Colour Marker	Effect
Ally	Dark blue	Joint defence and combined military action
Defensive alliance	Light blue	When one side is attacked, the other renders aid
Trade partner	Green	Both sides may trade resources
Vassal	Purple	Pays tribute to its overlord and provides military aid
Overlord	Deep purple	Manages vassal states and collects tribute
Neutral	Yellow	No special relationship
Distrust	Orange	Trade agreements become less efficient
Hostile	Red	May declare war proactively
Nemesis	Deep red	High probability of war

Diplomatic Actions#

Basic Actions#

Action	Requirements	Effect
Sign trade agreement	Both sides’ cities are adjacent or share a trade route	Both sides gain trade income
Propose alliance	Friendly relations and comparable military strength	Joint defence and combined military action
Form defensive alliance	Good relations and similar strength	Allies render aid when you are attacked
Declare war	No special requirements	Enter a state of war with the target faction
Sue for peace	You are at war with the target faction	Ends hostilities, may require ceding land or paying indemnities
Sign ceasefire	You are at war with the target faction	Temporarily halts hostilities

Vassal Actions#

Action	Requirements	Effect
Demand vassalage	Your strength far exceeds theirs	They become your vassal
Accept vassalage	The other side offers it of their own accord	Accept them as a vassal
Demand tribute	You have a trade agreement or vassal relationship	They pay you tribute on a regular basis
Release vassal	You are that vassal’s overlord	Dissolves the vassal relationship
Call for aid	You have allies or vassals	Ask allies to join your war

Special Actions#

Action	Requirements	Effect
Royal marriage	Friendly relations and marriageable royal members available	Establishes a blood tie and raises long-term friendliness
Exchange territory	You have a trade agreement or alliance with them	Both sides swap designated provinces
Exchange technology	Good relations with them	Share technologies already researched
Sign non-aggression pact	Neutral or friendly relations	Pledge not to declare war on each other for a set number of turns
Offer hostage	Relations need improving	Send a family member to the other side as a hostage

Diplomatic Strategy#

Strategy	Execution	Purpose
Build a trade network	Sign trade agreements with every friendly faction	Establish a stable income base
Conclude non-aggression pacts	Sign them with potential threats	Buy time to develop
Find allies	Ally with factions of comparable strength	Gain military support
Avoid multi-front war	Defuse potential conflicts through diplomacy	Concentrate on the main threat

Strategy	Execution	Purpose
Build a vassal network	Force weaker factions into vassalage	Expand influence and income
Divide the enemy	Use diplomacy to break up hostile coalitions	Destroy them one by one
Contest trade monopolies	Conquer provinces on key trade routes	Take control of trade income
Exploit rebellion	Make secret contact with rebel factions	Sow chaos inside the enemy’s lands

Strategy	Execution	Purpose
Build an empire	Control most of the map through vassals and direct rule	Achieve the final victory objective
Destroy the nemesis	Eliminate the most threatening nemesis first	Remove the greatest threat
Maintain peace	Stay at peace with minor powers	Concentrate resources on the main enemy
Prevent coalitions	Use diplomacy to stop hostile powers from uniting	Avoid fighting on two fronts

Factors Affecting Diplomatic Relations#

Factor	Positive Effect	Negative Effect
Trade agreement	+10 to +20 relations	Breaking trade: -10 to -15
Alliance	+20 to +30 relations	Betraying an ally: -50 to -80
Vassal relationship	+15 to +25 relations	Betraying an overlord: -60 to -100
War	—	-50 to -80 relations
Territorial dispute	—	-15 to -30 relations
Religious difference	—	-5 to -20 relations
Royal marriage	+15 to +25 relations	—
Territory exchange	+10 to +20 relations	—
Breaking a ceasefire	—	-40 to -60 relations
Releasing captives	+5 to +10 relations	—

Faction Diplomatic Preferences#

Faction	Natural Allies	Natural Enemies	Diplomatic Style
Western Roman Empire	Eastern Rome, Christian factions	Barbarian tribes, the Huns	Conservative defence
Eastern Roman Empire	Western Rome, Aksum	Sassanid Persia, the Huns	Economic diplomacy
The Huns	Other nomadic factions	All settled factions	Military deterrence
Sassanid Persia	Eastern tributary states	Eastern Rome, Arab tribes	Tributary control
The Visigoths	The barbarian league	The Huns, the Roman Empire	Raiding diplomacy

Diplomatic Negotiation Techniques#

Successful diplomatic negotiation requires understanding what the other side needs, and the leverage you hold in your own hands:

Technique	Notes
Understand their needs	If they are under threat, offering military aid makes agreement easier
Use fear	Overwhelming military strength is itself a bargaining chip
Negotiate in steps	Sign small agreements to build trust, then make larger demands
Use third parties	Apply pressure through your allies
Choose the moment	Negotiating right after they have lost a war is more favourable

Diplomacy Panel Operating Guide#

Operation	Notes
View relations	The map shows each faction’s relationship colour
Filter factions	Filter by type (allies, enemies, neutral)
View agreements	Review the diplomatic agreements currently in force
View threats	Assess each faction’s threat level toward you
Automated diplomacy	Let the AI handle part of your diplomatic business

Repairing Diplomatic Relations#

Method	Effect	Time Required
Give gifts	+10 to +30 relations	Immediate
Sign trade agreement	+5 to +15 relations	1-2 turns
Release captives	+5 to +10 relations	Immediate
Royal marriage	+15 to +25 relations	Requires a marriageable member
Common enemy	+5 to +20 relations	Requires a shared enemy
Religious improvement	+3 to +10 relations	Requires religious unity

Diplomatic Relationship Tier Explained#

Tier	Relation Range	Behavioural Tendency	Player Strategy
Mortal enemy	-200 to -100	Attacks proactively	Prepare defence or strike first
Hostile	-100 to -50	Attacks occasionally	Strengthen frontier defences
Cool	-50 to 0	Does not engage proactively	Negotiation is worth attempting
Neutral	0 to 50	No special behaviour	Ideal negotiation target
Friendly	50 to 100	Cooperates proactively	Alliance or trade is possible
Intimate	100 to 200	Deep cooperation	Marriage and military alliance possible

Marriage System In Detail#

Item	Notes
Marriage requirement	Relations of at least +50 and a marriageable member available
Relation bonus	+15 to +25 relations
Duration	Permanent, until that member dies
Strategic value	Prevents attack by an ally
Caveat	The married member may become an heir

Types Of Casus Belli#

Reason	Effect	How To Obtain
Territorial dispute	Declaring war costs no reliability	Holding disputed territory
Religious war	Support from religious allies	A different religion
Vassal liberation	Gains vassal support	Releasing a vassal state
Ally assistance	An ally asks you to join the war	An ally is attacked
Retaliatory attack	Morale bonus	Having been attacked previously
War without cause	Severe penalty	None

Vassal Management Guide#

Item	Notes
Vassal tribute	Gold and resources gained every turn
Vassal independence tendency	The lower relations are, the stronger the lean toward independence
Preventing revolt	Keep relations above +50 and send gifts regularly
Releasing a vassal	Grant independence in exchange for goodwill
Annexing a vassal	Annexation becomes possible at +100 relations

Diplomatic Action Priority#

Priority	Action	Reason
1	Peace with the weakest neighbour	Avoid multi-front war
2	Marry into a strong neighbour	Prevent being attacked
3	Establish trade agreements	Increase income
4	Form an alliance	A shared enemy
5	Declare war on a weak target	Gain territory and resources

Religious Diplomacy#

In the age of Attila, religion was not merely faith but also an important diplomatic tool. Religious differences between factions directly affect whether diplomatic relations can be established and maintained, and a natural, hard-to-bridge gap of trust exists between the Christian factions of Western and Eastern Rome and the pagan barbarian factions.

Religion	Main Distribution	Diplomatic Impact
Christianity	Western Rome, Eastern Rome	Naturally opposed to pagan factions
Sassanid religion	Sassanid Persia	Cool relations with Christian factions
Paganism	Barbarian tribes	Hard to build trust with Christian factions
Mixed faith	Frontier provinces	Religious conflict easily triggers revolt

Religious Diplomatic Tool	Notes
Religious intermarriage	Ease religious antagonism through marriage
Missionary cooperation	Spread the faith jointly with factions of the same religion
Toleration policy	Allow several religions to coexist domestically to stabilise order
Forced conversion	Impose a single religion after conquest, lowering short-term order

Diplomatic Traits Of Nomadic Factions#

The diplomatic logic of nomadic factions such as the Huns is completely different from that of settled empires; they rely far more on military deterrence than on treaties to hold relationships together. A Hunnic envoy backed by a great army on the border is far more persuasive than ten embassies loaded with gold.

Trait	Manifestation
No concept of territory	Territory changes constantly through migration, so treaties bind weakly
Dependence on raiding	Relations with neighbours are heavily affected by raiding behaviour
Deterrence diplomacy	Military strength is itself the main diplomatic chip
Vassal binding	More willing to accept military vassalage than economic alliance

Nomadic Diplomatic Technique	Notes
Display force	Raid periodically to show strength and force the other side to sue for peace
Absorb tribes	Take defeated tribes in as vassals and enlarge your forces
Avoid strength, strike weakness	Do not face off against a strong enemy for long; shift the direction of raiding
Sow discord among settled factions	Exploit religious and territorial disputes to fracture their coalitions

Vassal Economy In Detail#

Vassals offer more than military support; they are also a stable economic network. Sound vassal management brings an empire continuous income, and both Western Rome and Sassanid Persia can use a vassal system to compensate for their own economic weak points.

Vassal Benefit	Notes
Tribute income	Gold paid every turn according to the vassal’s economic level
Military support	Vassal armies can be called up for your wars
Trade bonus	Trading with vassals carries an extra bonus
Buffer zone	Vassal territory becomes a buffer between you and the enemy

Vassal Management Point	Notes
Control numbers	Too many vassals drives administrative costs up
Maintain relations	Send gifts regularly to keep loyalty
Prevent overgrowth	Limit vassal expansion so it cannot turn on its overlord
Annex at the right time	Once relations are good enough, annex the vassal to add strength

Common Diplomatic Events#

Event	Trigger Condition	Recommended Response
Alliance invitation	The other side faces a shared threat	Weigh the pros and cons before deciding whether to join
Territory request	The other side is stronger than you	You may refuse, but prepare a military response
Trade disruption	War or deteriorating relations	Find replacement trade partners promptly
Vassal betrayal	Vassal relations have fallen very low	Send troops to suppress it, or annex it outright
Spy exposed	Espionage activity is discovered by the other side	Apologise diplomatically to ease relations

Previous chapter: Campaign Guide