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You can build a flagship once your navy has at least 1500 active sailors.
For more of a step-by-step guide on how to build one, follow these steps:
Building a Flagship via the Production Interface
Open the Production Interface (hotkey: b)
Go to the Ship Building tab (hotkey: 2)
Click the “Build a Flagship” button
Pick a province where the flagship will be built
Select the name and ship type for your flagship
Choose up to three flagship modifications
Review and confirm your build order
Note: You can also capture other nations’ flagships in battle, but they’ll lose their mods and bonuses. They’ll just be regular ships with a special icon.
Flagship Modifications
Mods are the purpose of building a flagship. Most of them grant powerful bonuses to the flagship’s fleet.
A handful of nations have upgraded versions of the generic mods. Some have unique ones as well.
General Mods
Mod Name
Bonus
Additional Maintenance Cost
Mass Load Cannons
+50% Flagship cannons
0.5
Hull Sheathing
+50% Flagship durability
0.5
Trade Route Map
+1 Fleet trade power per ship
0.25
Command Aftercastle
+5% Fleet morale
0.5
Improved Crow’s Nest
+3 Fleet engagement width
0.5
Mortars
+1 Fleet siege bonus during blockade
1.0
Standardized Signal Book
+1 Fleet movement speed
0.5
Integrated Marines
+33% Army movement speed on and off ships
0.5
Flag Officers
+1% Monthly chance of admiral skill gain on mission
0.5
Spare Jolly Roger
+25% Fleet privateer efficiency
0.5
Captain’s Log
+100% Fleet prestige and naval tradition gained from battles
0.5
Exclusive Mods
Mod Name
Bonus
Additional Maintenance Cost
Exclusivity
Spanish Mass Load Cannons
+100% Flagship cannons
0.5
Castile, Spain
Spanish Grand Armada
-30% Fleet attrition
0.5
Castile, Spain
Spanish Treasury Convoy
+100% Fleet efficiency in “Hunt Pirates” mission
0.5
Castile, Spain
Portuguese Trade Route Map
+2 Fleet trade power per ship
0.25
Portugal, Brazil
Portuguese Navigators
+100 Fleet exploration range
0.5
Portugal, Brazil
Portuguese Fusiliers
+66% Army movement speed on and off ships
+2 Army combat penalty when landing
0.5
Portugal, Brazil
Portuguese Bombardier
-40% Fleet naval barrage cost
0.5
Portugal, Brazil
Dutch Courage
+10% Fleet morale
0.5
Holland, Netherlands
Scandinavian Flag Officers
+3% Monthly chance of admiral skill gain on mission
0.5
Denmark, Norway, Scandinavia
Recommended Builds
Portuguese Exploration Vessel
Flagship Type
Escort Fleet Composition
Mods
Bonuses
Light
2 Light Ships
Standardized Signal Book
Portuguese Navigators
[Optional] Portuguese Trade Route Map
+1 Fleet movement speed
+100 Fleet exploration range
+2 Fleet trade power per ship
Can explore the entire world within just 10–20 years
Incredibly useful right at the start
Should be scuttled once the world’s oceans have been fully explored
Portuguese Assault Cruiser
Flagship Type
Escort Fleet Composition
Mods
Bonuses
Light
As many transports as needed
[Optional] Heavies can temporarily join when doing a naval barrage
Standardized Signal Book
Portuguese Fusiliers
Portuguese Bombardier
+1 Fleet movement speed
+66% Army movement speed on and off ships
+2 Army combat penalty when landing
-40% Fleet naval barrage cost
Can quickly transport marines to distant provinces
Should not have any heavy ship escorts when transporting troops to maximize their fleet speed
Will stack with the “Portuguese Marines” naval doctrine, resulting in a massive -80% naval barrage cost
Will only need around 10 military mana instead of the regular 50 to do a naval barrage
May need additional heavy ships to barrage higher level forts
Portugal Gets the Cheapest Naval Barrages
Spanish Voyager
Flagship Type
Escort Fleet Composition
Mods
Bonuses
Light
2 Light Ships
Standardized Signal Book
Spanish Grand Armada
+1 Fleet movement speed
-30% Fleet attrition
Can attempt an early circumnavigation
Dutch Dreadnought
Flagship Type
Escort Fleet Composition
Mods
Bonuses
Heavy
Heavies and Galleys
Dutch Courage
Improved Crow’s Nest
Mass Load Cannons OR Hull Sheathing
+10% Fleet morale
+3 Fleet engagement width
+50% Flagship durability OR cannons
Can challenge Great Britain’s dominance at sea
Escort fleet can be a 1:5 ratio of heavies and galleys
As a frustrated otter who dreams of getting published, Louie instead wastes his life cuddling his cats. He spent his childhood playing Suikoden, grew up with Total War, and matured (somewhat) with EU4. He hopes to someday find a geopolitical JRPG with the 4X systems of a Paradox game.
