Naval warfare

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This page deals with naval combat mechanics. For information on the recruitment and maintenance of navies see navy. For details about ship types see naval units. For the state of war see warfare.

Naval warfare is the competition of sea-going power between nations at war. While a majority of warfare is land-based, the naval aspect of conflict can be incredibly influential in the spheres of trade, colonisation and conquest.

Sea battle interface

The naval combat interface

Like land warfare, naval combat occurs when opposing fleets confront each other in the same sea province. Also like land battles, these sea battles can go on for many days, so they should be considered not as a single engagement, but as two fleets maneuvering to gain wind, standing off and skirmishing before the fleets finally collide.

In EU4, there is no player involvement inside combat, but the interface now displays more information, showing among other information which ship is fighting which. The naval combat interface shows the strength of the two fleets engaged in the combat. Combat will begin with a contest of firepower, followed by shock action in which ships attempt to grapple or ram one another. This sequence will alternate until one of the fleets loses morale and is either routed or destroyed. The condition of each ship is expressed as a percentage, and hovering over a ship with the mouse cursor will produce a tooltip which identifies which opposing ship they are currently firing on, as well as their current morale, their strength, and the ship type.


Fleet composition

Main article: Navy#Organization

A fleet travels at the speed of its slowest ship, so mixing different types of ships in a fleet is inadvisable, unless the stronger ships act as escort for weaker ships, for example, transports. Galleys have doubled combat strength on inland seas and Cogs can transport military units.

The conclusion to a naval engagement

Engagement width

Since the patch 1.16, combat width for naval warfare has been introduced, it has a base of 25, and can be modified by the admiral's maneuver or by the admiral's traits.

  • Galleys, Transports and Light ships each occupy 1 combat width
  • Heavy ships occupy 3 combat width.

Combat sequence

Like land warfare, naval combat occurs when opposing fleets confront each other in the same sea province. Also like land battles, these sea battles can go on for many days, so they should be considered not as a single engagement, but as two fleets maneuvering to gain wind, standing off and skirmishing . A sea battle will last until one side is routed or annihilated. Patch 1.16 also introduced the concept of a naval combat width, and much like its land cousin it is the total number of ships that can engage the enemy at any one time.


Combat is divided into a series of 3-day phases. Phases alternate between Fire and Shock, with the Fire phase happening first.

Target selection

In combat each ship will try to find a target and make an attack.

Die roll

At the beginning of each phase, each side rolls a die. The result is used to determine the morale damage and hull damage inflicted by that side during each of the three days of that phase.

Hull damage

The amount of cannons of the attacking vessel affects the hull damage dealt and the hullsize of the defender decides how long it can stand the cannon fire. The Artillery Fire Modifier gives a bonus or penalty to damage dealt depending on if attacker or defender has a technological advantage.

  • Attacking unit modifier: The attack modifier from the attacking unit's technology, i.e. "Artillery Fire".
  • Attacking unit Combat Ability: Any Combat Ability bonuses the attacking unit has.

Morale damage

Morale is damaged both over time during a battle and also when a friendly ship is sunk. Several ideas decrease the amount of morale lost when a ship is sunk:

Morale hit when losing a ship.png Traditions Ideas Bonuses Policies
  • Naval idea 3: Naval Cadets
  • Portuguese idea 1: Legacy of the Navigator
  • Humanist-Maritime: The Citrus Statute
  • Betsimisaraka traditions
  • Galician idea 6: Sailors of the Cantabrian Sea
  • Naxian idea 2: Naxos Rules The Waves
  • Catalan ambition
  • Naval-Religious: Zealous Captains

Combat statistics

Diplomatic tech.png Cumulative diplomacy technology effects to navy

Dip Tech Level 0 3 7 8 12 18 22 25 27 29 31
Morale of Navies +2.0 +2.1 +2.4 +2.6 +3.0 +3.5 +4.0 +4.5 +5.0 +5.5 +6.0

Military tech.png Cumulative military technology effects to navy

Mil Tech Level 0 7 13 16 22 25 32
Artillery Fire +0.0 +1.0 +1.4 +2.4 +4.4 +6.4 +8.4

Max naval morale

The following contributes to the maximum morale of a nation's navy.

  • Naval Maintenance: Ranging from 20% at minimum maintenance (minimum of 0) to 100% at maximum maintenance (multiplicative modifier)
  • Naval Tradition: +25% at 100 Naval Tradition
  • Prestige: +10% at 100 Prestige, -10% at -100 Prestige
  • Power Projection: +10% at 100 Power Projection
  • Navy reformer advisor: +10%
  • Being the Defender of the Faith: +5%
  • Bankruptcy: -100%
  • War exhaustion: -2% per 1 war exhaustion
  • Ibadi IslamIbadi religion: +10%

Certain National Ideas, Idea groups and policies will bump naval morale.

Morale of navies.png Traditions Ideas Bonuses Policies
  • Alaskan traditions
  • British traditions
  • Genoese idea 2: The Lessons of Chioggia
  • Kono idea 3: Oyamazumi Shrine
  • Norwegian idea 1: Natural Seamanship
  • So idea 3: Fight for Tsushima
  • Luzon ambition
  • Quality-Maritime: The Organized Marines Act
  • Omani traditions
  • Bregenzer idea 7: The Lake Constance Navy
  • Chiba idea 7: Naval Reform
  • Corsican idea 2: The Battle of Meloria
  • Madyas idea 2: Legacy of Panai
  • Manx idea 4: Mann and the Isles
  • Ouchi idea 3: Protect Against Piracy
  • Sicilian idea 6: The Grand Navy
  • Dalmatian ambition
  • Mogadishan ambition
  • Ragusan ambition
  • Siddi ambition
  • Candarid traditions
  • Naval idea 7: Superior Seamanship
  • Quality idea 5: Naval Drill
  • Danish idea 3: Old Naval Traditions
  • Piratical idea 5: Elected Quartermasters
  • Exploration-Defensive: The Naval Secrecy Act
  • Religious-Maritime: Chaplains of the Fleet

Each point of naval tradition also increases naval morale recovery by +0.10%.

Combat ability

Combat ability is a value that is multiplied with the units' damage dealt (both for casualties and morale), but only for the specified type of unit.

Heavy ship combat ability improvement

Heavy ship combat ability.png Traditions Ideas Bonuses Policies
  • Naval idea 6: Oak Forests for Ships
  • British traditions
  • Butuan idea 6: Protect the Coastlines
  • Date idea 5: Red Seal Ships
  • English idea 1: A Royal Navy
  • Spanish idea 4: A Spanish Armada
  • Alaskan ambition
  • Genevan ambition
  • Innovative-Maritime: New Naval Tactics

Light ship combat ability improvement

Light ship combat ability.png Traditions Ideas Bonuses Policies
  • Veronese ambition
  • Alaskan traditions
  • Cham traditions
  • Ferraran traditions
  • Icelandic idea 4: Armed Merchants
  • Moluccan idea 6: Alliance with the Papuans
  • Arakanese ambition
  • Holstein ambition
  • Maritime-Plutocratic: The Protected Shipping Lanes Act
  • Hamburger traditions
  • Pattani traditions
  • Somali idea 6: Corsairs of the Red Sea
  • Sumatran idea 3: Spice Pirates

Galley combat ability improvement

Galley combat ability.png Traditions Ideas Bonuses Policies
  • Naval idea 2: Improved Rams
  • Venetian ambition
  • Aragonese traditions
  • Barbary Corsair traditions
  • Cebu traditions
  • Hosokawa traditions
  • Ionian traditions
  • Tunisian traditions
  • Berber idea 7: The Brothers Barbarossa
  • Cypriot idea 6: Repel the Corsairs
  • Italian (cU) idea 3: Mare Nostrum
  • Kitabatake idea 4: Kuki Suigin
  • Knights Hospitaller idea 4: Reconquista of the Sea
  • Moroccan idea 4: Defend the Coastline
  • Kono idea 5: Rule Over the Inland Sea
  • Maritime-Quantity: Streamlined Galley Production
  • Naxian idea 1: Maritime State
  • So idea 2: Wakou Tradition

Transport combat ability improvement

  • none

Unit pips

Main article: Naval units

Each ship has stats in three categories: Hull.png Hull, Icon ship cannons.png Cannon, and Icon ship speed.png Speed.

Hull is the defensive stat, and cannons the offensive stat. With the exception of Morale, every combat phase the hull/cannon pips are used against each other to calculate the number of hull damage of each combat phase.

Leader pips

Leaders are rated on a scale of 0-6 for each of the following skills:

  • Naval leader fire.png Fire, Naval leader shock.png Shock

The leader's skill is added to the dice roll of its respective phases.

Naval leader fire.png Traditions Ideas Bonuses Policies
  • Dutch idea 4: Instructie voor de Admiraliteiten
  • Naval idea 3: Naval Cadets
  • Ferraran idea 7: The Ferraran Arsenal
  • Norman idea 7: Great Commanders
  • Tunisian idea 5: Board of Captains
  • Corsican ambition
  • Madyas ambition
  • Naval-Innovative: The Nautical Education Act

Naval leader shock.png Traditions Ideas Bonuses Policies
  • Naval idea 1: Boarding Parties
  • Madyas idea 4: Masters of Maritime Warfare
  • Naval-Religious: Zealous Captains
  • Naval leader maneuver.png Maneuver

The leader's maneuver affects the movement speed of the fleet both on the map. Each point also grants 5% additional trade power when assigned to a fleet protecting trade in a trade node. Finally, it reduces attrition taken by 1% per skill level.

Naval leader maneuver.png Traditions Ideas Bonuses Policies
  • Madyas traditions
  • British idea 7: Britannia Rules the Waves
  • Mahri idea 4: Pilots of the Arabian Sea
  • Mogadishan idea 2: Somali sailors
  • Omani idea 6: Skilled Captains
  • Spanish idea 4: A Spanish Armada
  • Swahili idea 2: Monsoon Season
  • Innovative-Maritime: New Naval Tactics
  • Maritime-Offensive: Hold the Weather Gauge
The conclusion to a naval engagement

Concluding a battle

A naval battle ends when one side is either:

  • Reduced to 0 morale; or
  • Flees from combat; or
  • Annihilated

Upon victory, ships from the defeated fleet may be captured, depending on the difference between the two fleets' maneuver skill. Generally very little to no ships will be captured for leaderless (0 vs. 0 maneuver) battles.

If the defeated fleet still has ships remaining, it will escape to the nearest friendly port to repair and recover its morale. Naval battles, like land battles, may cause war exhaustion as well as affect warscore, naval tradition and prestige. Note that warscore gained from naval battles will generally be insignificant compared to those gained by its land counterparts.

Several ideas increase the chance of capturing ships after a battle:

Chance to capture enemy ships.png Traditions Ideas Bonuses Policies
  • Naval-Diplomatic: Terms of Surrender Statute
  • Betsimisaraka idea 5: European Pirate Communities
  • Knights Hospitaller idea 4: Reconquista of the Sea
  • Cornish idea 4: Pirates of Penzance
  • Dithmarscher idea 4: Expert Wreckers
  • Kono idea 7: Murakumi Suigun
  • Pattani idea 4: Lian Dao-Qian Band

Morale and strength


Morale is an important factor in fighting battles. Each turn of combat a unit will take a Morale hit. Once a fleet's average Morale value has been reduced to zero the fleet will attempt to retreat. Retreat cannot happen until both a fire and a shock phase have completed, so a fleet that has its morale reduced to 0 before that point will be destroyed.

If a fleet loses a battle while having low enough morale, they will be forced to retreat to a port of the nearest sea province. While retreating, it cannot be engaged in combat or be controlled until it reaches the sea province, nor will it repair. The fleet will also move 50% faster, and will recover morale at a normal rate during the retreat.

After every battle is fought a fleet must spend some time not fighting for its morale to recover.

Morale recovery

Every month when docked at a home port, a ship recovers a 10% of its maximum morale.

Certain National Ideas, Idea groups and policies will increase naval morale recovery.

Recover navy morale speed.png Traditions Ideas Bonuses Policies
  • Humanist-Naval: The Naval Inspection Act
  • Naval-Innovative: The Nautical Education Act
  • Religious-Maritime: Chaplains of the Fleet

Each point of naval tradition also increases naval morale recovery by +0.1%.

Unit strength

Unit strength is an important factor in fighting sea battles. Naval unit strength affects how long it can stand cannon fire before sinking. Each turn of combat a unit will take hull damage reducing its strength.

Galleys gain a bonus 100% strength in inland seas which are shown on the map below in pale blue.

Terrain map. Border pixels belong to the province to their southeast.

Ship repair

Fleets that have sustained damage will automatically repair up to their full strength when docked in an owned, allied, or in a province with fleet basing rights. There is a 'repair damaged' button that will detach damaged ships and send them to a nearby port to repair, when they are back up to full strength they will rejoin the fleet.

Main article: Navy#Ship_Repair

Fleet actions

Start patrolling

Start patrolling button.png The start patrolling button orders a fleet to loop its current movement order: when it reaches the final destination of its current set of movement orders, it will automatically head back to the point where the patrol was started. Patrol routes can include port visits, where the patrol stops until all ships are repaired. While the same function can be fulfilled by light ships assigned to protecting trade nearby, patrols are not limited by ship type, trade power, or trade range.

Raid Coasts

Raiding coasts is a naval ability added in the Mare Nostrum expansion which allows fleets belonging to nations of the Maghrebi culture group (Flag of Morocco Morocco, Flag of Tlemcen Tlemcen, and Flag of Tunis Tunis) and Flag of The Knights The Knights to raid the coasts of other nations for loot and sailors. Historically, this ability reflects the raids by Barbary pirates which were active in the 16th to 19th centuries. Raiding can provide a significant early-game boost to the income and sailor pools of nations that can do it.


Raiding coasts as Morocco.

Raiding a coast is something fleets can do at sea. To raid a coastal province, the following needs to be true:

  • the nation…
  • …has May raid coasts idea (i.e. countries with Berber national ideas or The Knights)
  • …must be able to place a fleet in a sea tile adjacent to the province, but doesn't need to be able to blockade the port
  • the target province…
  • …must be at most three sea tiles away from a province owned by the nation
  • …must have a development lower than or equal to the sail speed of the fleet (number of ships × speed of each individual ship)
  • …doesn't have the religion of the raiding nation
  • …doesn't belong to an ally or subject of the raiding nation
  • …doesn't have the “Raided Coast” modifier

After a province has been raided, its loot bar is emptied and the modifier “Raided Coast” is applied, which lasts for ten years. Each raided province will add a -25 relations penalty with the target country (down to -100), decaying by +1 per year.

The efficiency of raiding is reduced by fleets on pirate hunting patrol.


Fleets will automatically blockade a coastal sea province under hostile control while they are stationary and have no other orders.

Blockade power

The blockade power (sail speed in the tooltip) of a fleet is displayed after the Blockade enemy ports.png blockade icon in the fleet panel. It is mainly determined by the Icon ship speed.png tactical movement speed of the fleet's ships.

Each point of blockade power will be able to blockade one development point of a province.

Blockades will only take effect if there is enough blockade power to match the full development. If a fleet does not have enough blockade power to blockade all adjacent provinces under hostile control, it will assign its blockade power in precedence of:

  • Hostile province under a siege lead by any friendly force
  • Hostile province with the lowest development
  • Hostile rebel province with the lowest development

The detach blockade button (Detach blockade.png) in the fleet panel will detach a fleet of sufficient size to blockade all enemy ports neighboring the sea province.

Blockade efficiency

Blockade efficiency is determined by:

Blockade efficiency.png Conditions
+1% for every point of Navy tradition.png navy tradition

Ideas and policies:

Blockade efficiency.png Traditions Ideas Bonuses Policies
  • Maritime idea 7: Naval Fighting Instruction
  • Naval-Maritime: The Naval Supremacy Act
  • British idea 7: Britannia Rules the Waves
  • Omani ambition

Decisions and events:

Blockade efficiency.png Event modifier Trigger Duration
+20% Improved Blockade Tactics Maritime ideas event: Improved Blockade Tactics for 10 years.
−25% Blockade Standards Slipping Maritime ideas event: Slipping Standards
Option: ‘Well we can't expect them to operate at peak efficiency all the time’
for 10 years.

Effects of blockade

A blockade has a number of effects on that sea province and any neighbouring land provinces:

  • Siege: If the province is coastal and not blockaded, a -2 penalty is applied.
  • War score: Blockading an enemy's ports will drive up war exhaustion, lower war enthusiasm and increase the blockader's warscore, depending on the proportion of coastal base tax that is under blockade versus the nation's total coastal base tax.
  • Recruitment: +20% ship and regiment recruitment time.
  • Tax: -75% provincial tax income, -37.5% if province is looted.
  • Trade Goods Produced: -50% provincial trade goods produced. This penalty is applied as follows:
trade goods produced = (total positive production - 0.25 if under siege) * 0.5 if blockaded - 0.02 per war exhaustion
  • Spoils of War: Blockades will generate spoils of war in proportion to the amount income reduction in the province.
  • Restriction of movement: Blockading a sea province prevents any fleets in port from escaping without a fight.

Blocking a strait

To block a strait the following requirements must be met:

  • The conquesting alliance or a neutral nation have to control (owns or occupied) at least one side of the adjacent provinces
  • The conquesting alliance have to control the sea by a naval force (blockade efficiency doesn't matter)

However, if one nation controls both sides of the straight they can march over regardless of blockades.


  • A war participant controlling both sides of a strait: The Ottomans can cross the strait at Bosporus as long as they have control of Constantinople and Kocaeli even when the enemy controls the sea. Same system applies for the second strait between Edirine and Biga.
  • A neutral nation controlling a side of a strait: An Irish nation cannot cross the strait across the Irish Sea to Ayrshire in Scotland if the Irish nation is only at war with England (Scotland is neutral and gives military access to one of the war participants), and England controls the Irish Sea
  • However, if the Irish nation has called in an ally, say Burgundy, and Burgundy is in a separate war with Scotland and controls Ayrshire, then the first requirement is no longer fulfilled, and the Irish nation can cross the strait despite England having control of the Irish Sea

Sieging a province of a strait does not fulfill the first requirement.

Naval missions

Fleet missions are grouped together under a collective “Select Mission” button (Select mission.png) that allows the player to tell their fleets to;

  • Protect Trade
  • Privateer
  • Hunt Pirates
  • Explore
  • Hunt Enemy Fleets
  • Blockade Enemy Ports
  • Intercept enemy fleets

Protect trade

This mission is available to any fleet that contains light ships. It will add the trade power of the light ships in the fleet to any maritime trade node that the player already have some trade power in, provided that the trade node is within both trade range and supply range.

The trade power of light ships depends on ship model, and increases as diplomatic technology advances. Furthermore, it scales linearly with the naval maintenance slider, reaching full potential at maximum naval maintenance, but suffering a -75% penalty at minimum naval maintenance. AI nations do not suffer a trade power penalty to light ships from low naval maintenance.


This mission is available to any fleet that contains light ships. The fleet will hoist the jolly rogers and add the trade power of its light ships to a pirate nation in any selected trade node. Unlike the protect trade mission, existing trade power is not needed in a trade node to start a privateer mission.

Privateer efficiency

Light ships on privateer missions receive a +50% bonus to their trade power. Privateers do not inherit any national bonuses or penalties to global trade power. Factors such as overextension or halved trade power when collecting in foreign nodes are notably ignored. The trade power of privateers is instead affected by various privateer efficiency modifiers

Privateer efficiency.png Traditions Ideas Bonuses Policies
  • Naval-Maritime: The Naval Supremacy Act
  • Offensive-Exploration: Letters of Marque
  • Espionage idea 6: Privateers
  • Maritime idea 7: Naval Fighting Instruction
  • Cebu idea 5: 'The Place for Trading'
  • Mindanao idea 7: Pirates of Mindanao
  • Naxian idea 3: Archipelago Of Opportunities
  • Barbary Corsair traditions
  • Cornish idea 4: Pirates of Penzance
  • Dithmarscher idea 4: Expert Wreckers
  • Kono idea 7: Murakumi Suigun
  • So idea 4: Bahan Ship
  • East Frisian traditions
  • Gutnish traditions
  • Al-Haasa idea 7: Legacy of Ramah ibn Jabir
  • Arakanese idea 4: Magh and Ferenghi
  • Betsimisaraka idea 2: Pirate Ports
  • Cypriot idea 7: Raid Turkish Commerce
  • Malagasy idea 3: Pirate Ports
  • Montenegrin idea 4: Balkan Gusars
  • Moroccan idea 5: Protect Pirate Republics
  • Munster idea 6: Pirate Haven
  • Norman idea 5: Viking Raids
  • Novgorod idea 6: Funding the Ushkuiniks
  • Pattani idea 4: Lian Dao-Qian Band
  • Pomeranian idea 1: Legacy of Pirates
  • Sumatran idea 3: Spice Pirates
  • Berber idea 4: Corsairs
  • Sonoran idea 5: Taking What's Ours
  • Tunisian idea 3: Corsairs

The Enlist Privateers decision increase the Privateer efficiency.png by another +25%. It becomes available at 8 Diplomatic tech.png Diplomatic technology and requires the nation to have completed Maritime idea group.png Maritime ideas, a ruler with 3 Military power.png Military, as well as 50% of the Naval forcelimit.png force limit.

Each point of naval tradition also increases privateer efficiency by 0.25%. The total trade power from privateers is thus

privateer trade power = base trade power from light ships * 1.5 * (1 + naval maintenance modifier) * (1 + total privateer efficiency


Privateer fleets can only reach trade nodes in sea zones that are within trade range. A nation's trade range extends from cored provinces of the nation or it's subjects, as well as coastal ports of any nation that has granted it fleet basing rights.

Trade range can be increased by diplomatic technology, decisions, ideas, and policies:

Trade range.png Traditions Ideas Bonuses Policies
  • Ryukyuan idea 4: Maritime Commercialism
  • Swahili traditions
  • Trade idea 3: Merchant Adventures
  • Ayutthayan idea 5: Promotion of Trading links
  • Gujarati Princedom idea 7: Extend Trade Routes to Africa
  • Gujarat Sultanate idea 2: Jain Connections
  • Kono idea 6: Trade With Continental Asia
  • Malabari idea 1: Merchants of Southern India
  • Mesoamerican idea 7: Obsidian and Jade
  • Mogadishan idea 1: Indian Ocean Trade
  • Pacific Northwest idea 2: Dugout Canoes
  • South Indian idea 1: Merchants of Southern India
  • Traditions of The Hansa
  • Sumatran traditions
  • Evenk idea 2: Reindeer Herding
  • Dutch idea 2: Dutch Trading Spirit
  • Mamluk idea 1: Red Sea Trade
  • West Indies idea 4: The American Trade Hub


The privateer fleet increases the trade power of a pirate nation that acts as a collector in the trade node. This pirate nation will submit 40% of its earnings to the nations that commissioned the privateers contributing to its trade power. The presence of this pirate nation effectively reduces the share of trade value controlled by all non-pirate nations in the node. Income from privateering will be recorded in the economy window as spoils of war.

Any country that would have more than 20% of the trade power in the node without privateers will receive a casus belli against any nation that has sent privateers to that node.

Sending light ships on privateer missions against rivals is one of the easiest ways to accrue power projection. This can be especially useful to increase the power projection of the player beyond +25 for +1 free leader, or beyond +50 for +1Administrative power.png / +1Diplomatic power.png / +1Military power.png each month.

Activating a privateer mission will force the game to update a nation's power projection on the next game day. This will consequently update, among other things, the trade power in trade nodes and the nation's military force limits. Triggering an update like this can be useful when game stats are temporarily desynchronized due to certain actions, such as sending light ships to protect trade or changing local autonomy levels.)

Hunt pirates

This mission is available to fleets which contain at least one ship that isn't a transport. Fleets containing heavy ships or light ships may hunt pirates in any non-inland trade node; however, fleets containing only galleys (as well as fleets which are a mixture of galleys and transports) can only hunt pirates in nodes where all nearby sea provinces are inland seas, e.g. in Basra and Alexandria, but not in Hormuz.

The total number of guns of the ships, along with their sail speed, is used to find the efficiency at which they hunt the pirates. If the total number of guns and sail speed of the pirates is greater than they hunt at a lower efficiency. Their efficiency affects how much power pirates have in a node and the efficiency at which Berber nations raid coasts, at 0% when no fleet is hunting pirates, up to 99.9%.

Note that pirate fleets and fleets hunting pirates do not actually battle or otherwise damage each other, unless the countries that own the fleets are at war with one another.


This mission requires an explorer, and a total of 3 light and/or heavy ships. It sends the fleet to explore a region or a coast line, that can be choosen by either selection the region on the UI or clicking on the naval TI with the "explore" tab opened, and the player can attempt to circumnavigate the globe at diplomatic technology 9.

Main article: Colonization#Discovery

Hunt enemy fleet

The fleet will hunt enemy fleets in a specific sea region, that can be choosen by either selection the region on the UI or clicking on the naval region with the tab opened.

Blockade enemy ports

The fleet will blockade enemy ports and evade enemy fleets that are not significantly weaker ( Can be alteread by setting the fleet to be Bold )

Main article: Naval_warfare#Blockading

Intercept enemy fleets

This mission will have the fleet seek out enemy fleets near allied coastlines, focusing on troop transports.

Strategies and tactics


Due to the lack of stacking penalty, optimal strategic deployment in terms of combat results follows decisive battle doctrine strictly - concentrate all ships in one fleet, seek battle if one has superior naval assets, and hide otherwise.

However, other factors may complicate this. A country may be forced to divide their fleet if they have naval objectives other than destruction or suppression of the enemy navy, such as protecting (multiple) trade nodes, transporting land units by sea, exploring, patrolling for pirates, reconnaissance, blockading and so forth. If the country lacks naval supremacy compared to their enemies, they may be forced to risk losses, support fewer of these objectives at the same time, or leave the sea entirely for the duration of the war.

Bringing an enemy fleet to battle

A country with a naval advantage may wish to bring a reluctant enemy fleet to battle. This can be accomplished in several ways:

  • If the enemy fleet is docked at a port, they cannot be attacked directly. However, the fleet may be ejected by occupying (successfully sieging) that province, at which point the leaving fleet will enter into combat with any opposing fleet(s) in the corresponding sea province.
  • A small "bait" fleet may be used to lure the enemy into attacking, whereupon the main fleet can reinforce from a nearby sea province or port. This can also be used to lure fleets into or out of inland seas, where galleys have a relative advantage.
  • Light ships and galleys move faster than heavy ships and can catch an enemy fleet that contains heavy ships.