Colonization

As EU4 starts during the age of discovery, Colonization is an important feature available. Nations can explore and colonize the continents of the Americas (or a Random New World with Conquest of Paradise enabled), Asia, Africa and Australia, as well as Siberia and islands in the Pacific.

Objectives and prerequisites

The main benefit of colonialism is to improve the income generation and military logistics of the colonizing country. This is because colonized territories overseas can provide large boosts in trade income to the colonizing nation, as well as provide staging points for naval and land warfare around the world.

This is accomplished primarily by creating colonial nations, which are AI-controlled subject nations that will produce their own military and navy but will provide trade power and other benefits to the colonizer, and creating trade companies, which are semi-autonomous provinces that provide substantial trade bonuses in trade nodes that the colonizer can control. The type of subject nation created depends on its location in the world.

Any nation can benefit fully from overseas territories, even very distant ones, if they choose to make that territory into a state. However, provinces in overseas colonial regions should not be made into states, as the provinces are eventually ceded to the new colonial nation. Western technology nations will most likely prefer to make trade company provinces if possible instead of creating new overseas states, due to the bonus trade power and the ability to ignore religious differences. However, for many other nations, overseas states can sometimes be very profitable.

In order to colonize a nation must have:

• a colonist (from national ideas, idea groups, a Parliamentary issue, or a religious reform)
  • A special case is Russia with the Third Rome DLC, who can establish certain colonies without a colonist.
• an empty province to colonize (either adjacent to a core province, or within colonial range of a port)

It is recommended that a nation have:

• Ducats to cover maintenance of the colony (which rises quadratically if the number of colonies exceeds the number of colonists)
• a means of pacifying the natives (troops to guard it, or policies to lower their aggressiveness)

Discovery

Although some uncolonized provinces may be visible at the beginning of the game, much of both land and water is covered by terra incognita. Discovering these areas is essential to finding provinces to colonize.

How a nation goes about exploring depends on whether El Dorado is enabled or not. That said, the following factors are true regardless of DLC:

• A conquistador is required to explore on land (unless the country is at war; see below), and an explorer is required to explore at sea. These are special military leaders that are given pips as though the country had 80% as much tradition as it really does, in exchange for being able to explore.
• The “Quest for the New World” idea, the first idea in the Exploration idea group, is required to hire explorers and conquistadors. A handful of countries (notably Portugal) have an explorer in 1444 despite not having the idea; these leaders cannot explore in ocean provinces until Quest for the New World is unlocked.
• Norway, Iceland, Samoa and Tonga have national idea allowing to recruit explorers and conquistadors and allows them to explore without taking Exploration ideas.
• While at war, armies can enter all enemy provinces, even those hidden by terra incognita, assuming movement isn't blocked by forts or blockades. This can be done by clicking to move the army into a suspected province within the terra incognita; the army will begin to move regardless of whether they are able to complete the move. Movement into the province takes just as long as if it was being explored with a conquistador. When the move completes, the army either enters the province, or discovers that movement is blocked and stops moving; either way, the province is revealed.
• Conquistadors with high army tradition have a chance to discover adjacent provinces.
• Undiscovered land provinces have a chance per month to be discovered by owners of adjacent provinces (typically taking 3–5 years). Russia, colonial nations, nations with the Offensive-Expansion: The Pioneer Policy, and potentially custom nations have national ideas that make this discovery instant.
• Discovery of individual provinces will occur based on contact with other nations. In general, a province will be revealed to a country if:
  • The country in question explored any adjacent province at least 25 years ago
  • Any country that owns provinces undiscovered by the original country discovered the capital province of the original country at least 30 years ago.
  • Any neighbouring country, in the same culture or religious group as the original country, explored a province at least 75 years ago.

Map exploration can also be accomplished via the diplomatic action to Share Maps, which will reveal entire regions to the requesting nation at the cost of prestige if the nation being asked to Share Maps has already explored that region, and the nation requesting the maps has units in an adjacent region. Additionally, the diplomatic action Steal Maps (unlocked at diplomatic technology level 6 and which requires a spy network of 50 on that country) can be used to reveal regions in the same manner, but without the prestige cost.

	Traditions	Ideas	Bonuses	Policies
yes	Icelandic traditions	Exploration idea 1: Quest for the New World Norse idea 6: Leif's Legacy Norwegian idea 1: The Call of our Forefathers Samoan idea 7: Polynesian Triangle Trade Tongan idea 7: The Oceanic Empire	Hawaiian ambition	—

Exploration without El Dorado

• An army (of any size) led by a conquistador can be moved into land provinces covered by terra incognita, thus discovering them. If that land is owned by another country, the conquistador will merely discover the province when movement finishes instead of actually moving into it, unless that country grants military access. Conquistadors can move through primitive nations (those in New World technology groups that have not yet reformed their governments/religions) even without access.
• A fleet (of any size) led by an explorer can be moved into sea zones covered by terra incognita, thus discovering them. Upon entering a sea zone, they also have a chance to discover coastal provinces adjacent in that zone (increased by the explorer's Maneuver skill).

Exploration with El Dorado

• Land exploration largely follows the same process as it does without El Dorado, as listed above.
• If the country's own capital is not in a colonial region, an army (of any size) led by a conquistador in a colonial region can be sent on a mission to Hunt for the Seven Cities of Gold via the army interface. The army will then automatically move through terra incognita in the region, uncovering it as it moves, with a chance to trigger various special events. Exploring provinces owned by primitives, whether using Hunt for the Seven Cities or not, does not require military access.
• Any fleet led by an explorer and containing at least three light and/or heavy ships can be sent on an exploration mission via the fleet interface and will do so automatically once assigned.
  • The fleet can be sent to explore 'the waters' of a region, meaning the explorer will discover open sea and coastal sea zones, but will not discover land provinces; or they can be sent to explore 'the coast' of a region, meaning the explorer will explore and reveal coastal land provinces in that region. Typically, 'the waters' of a region must be explored first before 'the coast' becomes available as a mission. While exploring open sea, the explorer will discover all sea zones in that region that are in range before returning. While exploring a coastal sea zone, they will discover all coastal provinces bordering that sea region before returning. Right-clicking on unexplored ocean will automatically start the exploration mission for the appropriate region, as long as part of it is within range.
    • Fleets on exploration missions do not suffer attrition, but only missions to regions within their country's colonial range can be explored this way. Fleets on exploration missions cannot be recalled or reassigned during the mission, only disbanded, which may kill the explorer. Explorers may trigger certain random events while on missions. If the explorer dies, the fleet will automatically return home but will take attrition while doing so.
  • An explorer can also be sent to circumnavigate the globe. The fleet will take naval attrition as normal while on this mission, and may sink, killing the explorer as well. Like other exploration missions, fleets sent on missions to circumnavigate the globe cannot be recalled or reassigned during the mission; ample preparation beforehand is advised before beginning the mission. The first nation worldwide to have an explorer successfully circumnavigate the globe receives +100 prestige. Any other nation that completes this mission afterwards receives +10 prestige. This exploration mission can only be completed once per nation, though it can be repeated if failed.

Colonists

A colonist envoy is required to start a colony.

Gaining colonists

	Traditions	Ideas	Bonuses	Policies
+1	—	Expansion idea 1: Additional Colonists Expansion idea 6: General Colonization Law Exploration idea 2: Colonial Ventures American idea 3: Manifest Destiny Andalusian idea 6: Expeditionary Sentiment Asturian idea 4: Voyage to the New World Australian idea 1: Outback Stations Canadian idea 3: Settling the Interior Carib idea 5: Carib Seafarers Castilian idea 4: Inter Caetera Leonese idea 3: Conquest of the New World Majapahit idea 4: Nusa Tenggara Colonies Nizhny Novgorod idea 5: To The East! Norse idea 6: Leif's Legacy Norwegian idea 2: Pioneer Spirit Spanish idea 2: Inter Caetera	Hadramhi ambition Icelandic ambition Kiwi ambition West Indies ambition	—

• +1 Completing the Spice Islands mission [Root.GetAdjective] Dominance.
• +1 Completing the New World mission Native Colonization.
• +1 Completing the Oceania mission Colonization of Oceania.
• +1 for 100 years for completing one of the following missions: Mutapa mission Uncover the South, Jolof mission Take over Futa Jallon, Kongo mission Develop Kongo. This colonist gets removed if the country acquires a colonist from another source.
• +1 for 50 years for completing the Adal mission Eliminate the Nubian Copts. This colonist gets removed if the country acquires a colonist from another source.
• +1 for 50 years for completing the Kilwa mission The Uncharted South.
• +1 for 25 years for completing the Mali mission Ko Mamadi's Ambition.
• +1 Having a Parliament government and passing the "Charter Colonies" issue, duration 10 years.
• +1 from Mesoamerican religious reforms: Tribal Expansion for Mayan and Nahuatl, and Expanded Mitma Policy for Inti.
• +1 from being Alcheringa and selecting the Baiame cult.
• +1 for 10 years from Protestantism event "Protestant Diaspora", received by the colonial parent.
• +1 Being a Self-Governing Colony.

Native policies

An example of native policies in game

Native policies allow a nation to decide on their foreign policy regarding indigenous natives in colonizable provinces around the world. A native policy must be chosen when a nation unlocks their first colonist (from any source). The original selection is free. Changing native policies afterwards costs −1 stability, but has no cooldown.

Native Coexistence Policy grants a −100% bonus to the chance to get a native uprising, effectively reducing aggressiveness in all colonizable provinces to 0. This policy is beneficial for when a nation's armies are busy elsewhere and can't be wasted sitting on a colony, when manpower is too precarious for constant skirmishes, when a nation is too poor to maintain a garrison, or for native and Sub-Saharan nations who may actually lose battles with natives in the early game. This policy also prevents natives from attacking exploring armies led by conquistadors, negating the need to field more than one unit in an exploring army or spend ducats on maintenance for said army.

Native Trading Policy grants a −50% bonus to native uprising chance (effectively reducing aggressiveness by half) and +50% to native assimilation.

Native assimilation means that the goods produced in a colonized province will increase by a factor equal to ${\text{native population}}\div 20,000$, rounded down, once that colony becomes a full province. The native trading policy increases this bonus by +50%. This choice could be useful if playing France, which also has a bonus to native assimilation in their national ideas (and also receives a reduction to native uprising chance that makes it a more advantageous Native Coexistence Policy), or for any nation that can handle a few revolts and will be coring and taking full control of the province when completed, or any nation controlling a significant percentage of the generated trade value.

Native Repression Policy grants a bonus +20 global settler increase. While this policy makes for more rapid early colonization, the bonus is not overwhelming at higher technology levels. The provinces will require garrisons as native uprising chance is not reduced.

Colonial range

The range from which a nation can establish a colony from a core is called the colonial range. It is measured from that nation's nearest unoccupied core province (hence, during war, coring range may be significantly reduced until key provinces are unsieged from enemy occupation), and it expands depending on the diplomatic technology level of the nation as well as events, advisers, missions, policies, ideas, and other bonuses. Fleet basing rights from third countries do not extend this range.

This range also controls how far explorers can go on exploration missions. If a nation has no ports, they can only colonize adjacent land provinces, regardless of colonial range.

To check the range to a given province, change the map mode to "Colonial Range", and hover over the province of interest. The map will show green for in range and red for out of range.

Basic colonial range increases over time as diplomatic technology improves:

Dip tech lvl	Base	3	7	9	11	15	17	19	23	26
	60	+100	+115	+50	+100	+50	+50	+50	+150	+200
Cumulative tech	60	160	275	325	425	475	525	575	725	925

These base technology levels of colonial range can be augmented by the following bonuses and policies:

	Traditions	Ideas	Bonuses	Policies
+50%	—	Exploration idea 3: Overseas Exploration	—	—
+40%	—	Hawaiian idea 7: Legendary Voyagers	—	—
+33%	—	Norwegian idea 1: The Call of our Forefathers	—	—
+25%	—	Livonian idea 5: Livonian Colonization	—	Indigenous-Trade: Commercial Tribes
+20%	—	Kilwan idea 1: Kilwan Latitude Staves Norman idea 4: Descendants of Seafarers Portuguese idea 1: Legacy of the Navigator	—	Exploration-Plutocratic: The Colonial Companies Act
+15%	—	Couronian idea 5: Couronian Colonization	—	—
+10%	—	Fijian idea 2: Lutunasobasoba and Degel Iwi idea 1: Sons of Kupe	—	—

The quickest way to temporarily increase overall range is to appoint a Navigator diplomatic advisor who provides a +20% colonial range bonus.

Travel time

The speed at which a nation's colonists travel to claim and establish colonial territory is related to the travel time of merchants and diplomats. It is based primarily on distance from the capital but, unless the target province is directly land connected to the capital, colonists travel by sea. The actual route taken is the shortest sea distance from either the capital's port (or, if it is inland, a port that is directly connected to it) to either the target province's future port location or the port that is closest to the target province.

Example: Portugal's capital is Lisboa. In order to colonize Pipil (839), a province next to the Mayan nation of Kiche on the west coast of Central America, a colonist would first travel all the way south to Cape Horn in South America, then back north to reach Central America again. However, if Portugal colonized Chortli (2637) first, which is the province north of Pipil but on the east coast of Central America, then a Colonist subsequently travelling to Pipil would have its travel time dramatically reduced.

Colonist travel time can be difficult to predict due to their coded preferences for travel. For port provinces not directly connected to one's capital, colonists will always travel by sea to where the port will be located, even if it would be faster to travel overland from another port (or the province borders both coasts like in Central America). For inland provinces not directly connected to the capital, colonists always travel to the closest non-blockaded port to the target province even if it would be quicker to travel cross country from a port on a different coast. These unusual rules can sometimes account for extended colonist travel time.

Nations in colonial regions, especially North America, can experience unusually long travel times for colonists. Normally, this is because if a nation's capital is coastal, colonists will always prefer to travel by sea, even if travelling by land would be faster. It may be prudent to move the capital inland if this becomes an issue.

Colonists travel across open sea much faster than through land or coastal sea provinces. For example, European colonists can reach the Caribbean faster than Sub-Saharan West Africa, even though it is physically much farther away.

All modifiers to envoy travel time also change the travel time for colonists. Colonists return instantly the day after either the colony becomes a city or they are recalled.

As soon as any nation chooses to send a colonist to a province, no other nation can send a colonist to that province unless the colony is later destroyed before completion, even if the colonist will actually arrive two years later. Two nations cannot 'race' and see which colonist will arrive first to the province.

	Traditions	Ideas	Bonuses	Policies
−33%	—	Spanish idea 5: Casa de Contratación	—	—
−25%	Brazilian traditions	Influence idea 6: Postal Service Ajami idea 4: Persian Language and Court Culture Ilkhanid idea 4: The Yam Kamilaroi idea 4: Dhulu Kongo idea 4: Diplomacy With European Monarchs Mongolian idea 5: Yams of the Great Khan Sulu idea 3: Across the Sulu Sea West African idea 6: The Great River	—	Infrastructure-Espionage: Spy Network Act
−20%	—	Expansion idea 4: Viceroys Plains Native idea 7: Horse Riders	—	—
−10%	—	Great Yuan idea 5: A Thousand Miles as if at Home	—	—

Population

Once a colonist arrives in an unowned province the population starts at 10. Colony populations grow at a base rate depending on the nation's global settler increase value, which is largely dependent on diplomatic technology level but also by some ideas and other modifiers.

In addition, as long as a colonist remains in a colony, they have a chance each month (modified by colonist chance) of bringing in 25 additional population, speeding growth greatly.

Once a colony reaches a population of 400, it will be randomly assigned a trade good based on a weighted list of goods available in that geographical region. This list can be seen via hovering over the large question mark icon in the uncolonized province screen, or by hovering over the province in the Trade Goods map mode. If the colony is abandoned or otherwise destroyed at this stage, the trade good reverts to Unknown (i.e. the weighted list), meaning that a different trade good may be randomly assigned in following attempts at colonising the province.

A colony becomes a full city when its population reaches 1000, and is destroyed if its population reaches 0; this will happen if a colony is abandoned, but can also happen due to attacks by natives, events and colonies being destroyed by other countries in a war. Resending a colonist is required to restart these colonies.

Colonists can be sent and recalled to other colonies in progress as many times as is warranted. Colonists can even be sent to colonies of enemy nations that have been seized by using the “Seize Colony” army option (which costs 25 military power). A captured colony retains the culture and religion that it had previously, but a colonist will convert to those of its new owner in the same circumstances as it would otherwise.

Global settler increase

Colonies grow by a flat number of settlers each month. This number is the nation's global settler increase, which is the number of additional colonists added to a colony per year. For example, if the country's global settler increase plus the province's local settler increase is 15 per year, the colony will get one settler most months but two settlers every fourth month, for a total of 15 for the year. Diplomatic technology provides additional global settler increase:

Diplomatic technology	Global settler increase (cumulative)
1	10
3	25
10	35
15	50
23	75
26	100
32	150

Global settler increase is further improved by the following bonuses:

	Traditions	Ideas	Bonuses	Policies
+30	—	Central Algonquian idea 7: Land of the Dawn Eastern Algonquian idea 7: Back Before Spring Federation idea 7: Sunrise Invasion Iroquoian Federation idea 7: The Grand Council Muskogean Federation idea 7: Meritocratic Leadership Siouan Federation idea 7: Across the Land	—	—
+25	Australian traditions	Alaskan idea 2: The Hard Push East Kiwi idea 5: The New Zealand Company Native idea 7: Great Winter Hunts	Castilian ambition	—
+20	—	Expansion idea 3: Faster Colonists Acehnese/Pasai idea 7: Settle the Islands Balinese idea 1: Island Settlers British idea 2: City Upon a Hill Bruneian idea 5: Settle the Islands Colonial idea 6: New Frontiers Japanese idea 6: Kaitakudan Malayan Sultanate idea 7: Settle the Islands Malayan idea 1: Settle the Islands Moluccan idea 5: Dominance over the Outer Islands Northeastern Woodlands idea 7: Crane Clan Siberian idea 7: Hunting Expansion	Hawaiian ambition	—
+15	Mexican traditions	Cham idea 4: Cham Migrations Danish idea 6: Colonial Ventures Munster idea 5: Fairer Shores Portuguese idea 4: Land Before Faith Thomondian idea 7: Thomond's Overseas Ambition Tongan idea 7: The Oceanic Empire	Ando ambition	Expansion-Exploration: Colonial Expansion
+10	—	Exploration idea 4: Land of Opportunity Livonian idea 5: Livonian Colonization	—	Administrative-Exploration: The Colonial Administration Act Exploration-Plutocratic: The Colonial Companies Act Humanist-Exploration: Native Assimilation Act Quantity-Expansion: Colonial Garrisons

and the following static modifiers:

	Modifier
−X to +X yearly	Colonial maintenance
−5 yearly	No adjacent province controlled
−10 yearly	Arctic
−10 yearly	Arid
−10 yearly	Tropical
+10 yearly	Treaty of Tordesillas (Catholic country settling a colonial region assigned to them by the Pope)
−20 yearly	Violation of Treaty of Tordesillas (Catholic country settling a colonial region assigned to a different mother country by the Pope)
+20 yearly	Trading in Cotton
+10 yearly	“Grant New World Charter” Burghers estate interaction
+15 yearly	“Heretics Deported” Protestant Aspect of Faith
+10 yearly	Alcheringa nation with cult of Baiame selected
+10 yearly	Tengri nation with Orthodox syncretic faith
+20 yearly	“Charter Colonies” Parliament issue
+20 yearly	“Native Repression” native policy
+50 yearly	Portuguese “Colonial Growth” splendor ability during the Age of Discovery ( Portugal only, requires Mandate of Heaven)

Settler chance

If a colonist is in a colony there is some probability that 25 settlers reach the colony at the beginning of each month. Each 1% of probability is on average equivalent to 3.0 settlers per year (0.01 chance/month × 12 month/year × 25 settlers). The chance of a colonist attracting new settlers is determined by the following:

Modifier	Chance	Mean settlers/year
Base + Base Value	10%	30
Same continent	5%	15
Per 100 population ("colony level")	−1%	−3
Per percentage point production efficiency	0.2%	0.6
Per point native uprising chance	−1%	−1.5
Same religion	1%	3
Same culture	1%	3
Same culture group	1%	3

There are a few policies that can increase the chance of new settlers.

	Traditions	Ideas	Bonuses	Policies
+10%	—	Exploration idea 6: Free Colonies	—	—
+5%	—	Expansion idea 6: General Colonization Law	—	Administrative-Exploration: The Colonial Administration Act Exploration-Innovative: Benign Neglect Horde-Exploration: Steppe Nomad Migrations Offensive-Expansion: The Pioneer Policy

	Conditions
+5%	with "Grant New World Charters" Burghers estate privilege
+0.1%	per home province development when expelling minorities

Important modifiers to colony growth

Climate

The location and climate of a potential colony will affect the rate of growth of the colony. Colonies in arid, tropical or arctic locations will receive a −10 global settler increase penalty, and a colony with no adjacent colonies of that nation will receive a further −5 penalty.

If controlling an area ahead of other colonizers is a concern, a nation can prefer to colonize locations with favorable terrain, but other major factors such as the number of hostile natives and the presence of a Center of Trade need to be considered as well.

Events

Main articles: Exploration idea group events, Expansion idea group events

The Exploration and Expansion idea groups unlock several events that can trigger to modify colony growth rate or size directly, and can be either beneficial or detrimential. The events Colonist Rush and Colonial Enthusiasm give the following powerful, but temporary, modifiers to colony growth:

• Gain “Colonial Enthusiasm” modifier for 10 years:
  • +5% Colonist chance
  • +25 Global settler increase

Some nations that were historical colonizers, notably Spain and Portugal, have unique missions or events that will improve settler growth.

Treaty of Tordesillas

With El Dorado DLC, the first nation to form a Catholic colonial nation (that is, to core 5 provinces in a colonial region, assuming its own capital is not within a colonial region) while the Papal State's opinion of them is positive will be assigned that region. That nation and their associated colonial nation will receive a +10 increase to settler growth within the region. A single nation can have any number of colonial regions assigned to them by the Pope.

If another Catholic nation (even one with its capital in a colonial region) starts colonizing a province in that region, they will receive a severe penalty for having "Violated the Treaty of Tordesillas". This include a −20 Local Settler Increase penalty when colonizing that colonial region, as well as a one-time −10 papal influence penalty and a −50 modifier to the Papal State's opinion of that nation. Also, nation that has the claim receive -200 modifier to the opinion of them, with yearly decay of +1. Colonies that are in progress when the Pope assigns a colonial region to another nation do not count as having violated the Treaty of Tordesillas, only colonies started after a colonial region has been assigned.

These modifiers can only affect Catholic nations; nations of other religions can receive neither the bonuses nor the penalties.

If the nation owning a colonial region is completely annexed, the colonial region will revert to no nation having a colonial claim, and a new nation can be assigned the region by creating a colonial nation or owning a current colonial nation in the region.

The Treaty of Tordesillas mechanic attempts to represent the historical treaty made between Portugal and Spain which assigned lands east or west of a certain longitude to Portugal or Spain, respectively.

Native policies

With The Cossacks expansion, a nation must select a native policy that represents how that nation will interact with native peoples around the world. This only refers to the uncivilized indigenous native populations in uncolonized provinces, not to any Native American, African or Indonesian nations.

If a nation selects Repression, they will receive a bonus +20 global settler increase, at the cost of more uprisings by the natives. The other two policies do not affect settler increase.

“Natives Encountering our Colonies”

Main article: Natives events

Without The Cossacks, when a Christian state establishes a colony in the New World with at least 300 natives, it triggers the “Natives Encountering our Colonies” event. All three options enable events that can lead to temporary boosts to global settler increase and colonist chance, and will unlock other events related to the decision chosen. Non-Christian nations cannot receive any of these events.

Maintenance

Colonial maintenance is the money that a nation spends in maintaining its colonies, and can be adjusted through a slider in the Economy tab. The base maintenance cost (at 100% colonial maintenance) is 2 ducats per month. A country can maintain one colony for each colonist it has at this base cost. The $i$th colony beyond that many costs an additional $2\times i^{2}$ ducats per month on top of the base, for a total multiplier as follows:

Colony over cap	Cost per month for that colony
1st	2×
2nd	5×
3rd	10×
4th	17×

No idea or policy decreases colonial maintenance for normal colonies, but the cost when expelling minorities can be reduced.

Cumulative cost for colonization maintenance by virtue of colonists and colonies:

	1	2	3	4	5	6	7
1	2	2	2	2	2	2	2
2	6	4	4	4	4	4	4
3	16	8	6	6	6	6	6
4	36	18	10	8	8	8	8
5	70	38	20	12	10	10	10
6	122	72	40	22	14	12	12
7	196	124	74	42	24	16	14
8	296	198	126	76	44	26	18
9	426	298	200	128	78	46	28
10	590	428	300	202	130	80	48
11	792	592	430	302	204	132	82
12	1036	794	594	432	304	206	134
13	1326	1038	796	596	434	306	208
14	1666	1328	1040	798	598	436	308
15	2060	1668	1330	1042	800	600	438
16	2512	2062	1670	1332	1044	802	602
17	3026	2514	2064	1672	1334	1046	804
18	3606	3028	2516	2066	1674	1336	1048
19	4256	3608	3030	2518	2068	1676	1338
20	4980	4258	3610	3032	2520	2070	1678

Siberian frontiers do not cost maintenance and do not count towards a country's colony count for the purpose of increasing costs.

Natives

Colonizable provinces are usually occupied by natives, who may attack a colony there, depending on several factors. Natives are also very likely to attack land units passing through their province, regardless of whether the province is colonized. However, these attacks depend on Aggressiveness, so taking the “Coexistence” Native Policy disables these random attacks and taking the “Trading” Native Policy reduces the chance of an attack occurring by half. Native tribes do not experience native uprisings.

Population

Native population in 1444.

The size of the native population determines how many native regiments attack at a time. The native population in a province can be reduced permanently using the  Attack Natives military action, which costs a small amount of military power proportional to the population, aggressiveness, and ferocity of the natives. The action may need to be performed multiple times in order to completely drive out the local population, as native regiments that break from combat due to low morale are not killed and so return to the 'population' of the colony.

Native assimilation

When a colony becomes a full city, it will gain a bonus to goods produced called the “native assimilation bonus”, which depends on the remaining native population. This bonus is given by:

${\text{Native assimilation bonus}}={\frac {\text{Native population}}{20000}}$

So a colony with 1400 natives in the province should gain $1400\div 20000=0.07$ goods produced when the colony completes. A population of 4000 natives would give +0.2 goods produced, equivalent to one level of production development. Because of this, it is usually beneficial to leave the native population alone if the colony can be protected by an army.

Bonuses to “native assimilation” increase this bonus. For example: taking the Native Trading Policy increases the assimilation bonus by +50%, effectively increasing the goods produced in the completed colony by half of what it normally would have been due to native population. So a colony with 1400 natives in the province would gain 0.105 goods produced when the colony completes (e.g., $1400\div 20000\cdot 1.5=0.105$).

	Traditions	Ideas	Bonuses	Policies
+50%	—	Cascadian idea 2: Chinook Jargon French idea 4: Native Trading Principles Vermont idea 3: American Frontier	—	Humanist-Exploration: Native Assimilation Act

• The British mission “Colonize the Caribbean” gives +25% native assimilation for 15 years.
• The theocracy government reform “Mission to Civilize” gives +35% Native assimilation
• The clergy privilege “Establish New World Missions” gives +50% Native assimilation
• The Native Trading Policy gives +50% Native assimilation

Native uprising

When colonizing a province there is a chance for the native population to rise up aggressively in an attempt to destroy the colony and expel the foreign invaders. If a native uprising happens, native regiments equal to the native population in the province will appear and attack any military units in the province, or begin a siege of the province if there are no military units stationed in it. If the siege is finished (which will take one month), the settler population in the colony is reduced by −100 per regiment of natives, which can destroy the colony completely. After the siege is finished the native regiments will disband, regardless of whether or not the colony survived. After an uprising (whether successful or not), there is a one-year cool-down period during which there is no chance of another native uprising from the province. After this period the chance of an uprising returns to what it was before.

	Traditions	Ideas	Bonuses	Policies
−50%	—	Cascadian idea 2: Chinook Jargon French idea 4: Native Trading Principles Vermont idea 3: American Frontier	—	Expansion-Exploration: Colonial Expansion Horde-Exploration: Steppe Nomad Migrations

• The theocracy government reform “Mission to Civilize” gives −50% Native uprising chance.
• Completing the spice island mission “[Root.GetAdjective] Dominance” gives a permanent −50% Native uprising chance.
• Tribal nations do not experience native uprisings at all.

Aggressiveness

Native aggressiveness in 1444.

Aggressiveness ranges from 0 to 10 and determines how likely the natives are to attack a colony. Each point of aggressiveness gives a 1% chance of a native uprising happening per month. Taking the Native Trading Policy applies −50% to the chance of uprising, effectively halving aggressiveness. Taking the Native Coexistence Policy will apply −100% to the chance of uprising, effectively removing native aggressiveness and the chance of an uprising in all provinces.

Ferocity

Ferocity ranges from 0 to 10 and is independent of aggressiveness. Natives regiments in the province get 0.2% military tactics per point of ferocity.

Units

Natives use low-tech units:

Area	Name	Off.	Def.	Off.	Def.	Off.	Def.	Total pips
Americas	Native American Archer	1	0	0	0	1	0	2
Africa	African Spearman	1	1	0	0	1	0	3
Asia	East Asian Spearman	1	0	0	0	1	0	2
Arctic	Archer Cavalry	1	0	0	0	1	1	3

Occupation

During a war, a colony can be occupied like any province. The development of a colony through normal growth will continue unabated, but a colonist present in the province will be sent back to the colony's owner. An army standing in an occupied colony will have the option to Seize Colony for 25 military power. The colony ownership will transfer to the nation that used the action. The colony will keep the culture and religion of the previous owner until a colonist from the new owner reaches the colony. The colony will cost its new owner money the same as if it had been colonized by them, including the increasing costs of holding more colonies than the number of colonists.

An alternative option is the military action Burn Colony for 5 military power. The colony is completely destroyed and the province becomes, once again, an uncolonized province.

Since a colony keeps growing under occupation, it is possible that it will become a full colonial province while being occupied. Unless the 'Seize Colony' option was used earlier, the 'finished' province will belong to the original owner. This can be used to steal growing colonies to save war score for another action in the peace treaty or by non-colonizer nations to gain a colonial foothold.

Colonial provinces

Once colonization is finished, a colony becomes a city with a territorial core. The owner will now be able to do anything that could be done with a normal territory, such as build buildings, recruit troops, build ships, and improve the province's development level. The nation will also now be able to trace coring and colonial range from it. The area can be made a state and fully cored like any other province, though the state upkeep is typically quite high due to distance from the capital.

If the finished colony is in a colonial region and the country's capital is not in a colonial region, the colonizing nation will retain control of the province until a total of 5 provinces are colonized (or conquered and made territorial cores) by that nation in the same colonial region. All provinces in the colonial region will then be ceded to a newly formed colonial nation, with the most developed province becoming the capital, and any cores converted to full cores of the colonial nation. Any further provinces that are conquered (even if not cored) or colonized in that colonial region will be ceded to the colonial nation after one day. Territorial cores are still converted to full cores and state provinces are not immune, so making states in colonial regions is generally a waste of administrative power (unless the country's capital is itself in a colonial region).

The provinces will generally keep the native religion and culture. They will change to the colonizer's (or that of a minority being expelled) when settlers first arrive, or when a colonist attracts additional settlers (i.e. the check for colonist chance succeeds), in the following situations:

1. It is in North or South America, or the random New World.
2. It is anywhere else and neither Wealth of Nations nor Dharma is active.
3. The province has a land connection to the colonizer's capital and is on the same continent.
4. The province has no religion or no culture (usually because it has no natives).
5. There are at least (natives − 100) settlers.

The province will return to its native religion and culture if the colony is abandoned.

Some important consequences follow from the above:

• A Siberian frontier east of the Urals (i.e. in the continent of Asia, rather than Russia's capital which is in Europe) will not change culture and religion if it doesn't change as soon as it's established, because colonist chance does not apply there. The same is true if any different-continent old world colony grows without a colonist.
• Provinces on another continent (besides the new world) with fewer than 1000 natives will usually change; those with about 1000 will change with a probability approximately equal to settler chance; and those with more usually will not change.
• A same-continent colony established without a land connection may change later (but only via settler chance) if a land connection is established.
• Colonies that are conquered from another country will only change if a colonist is sent to them.

Colonies, and provinces that became cities by colonization that are conquered from another country, do not cause overextension, even if left uncored. Provinces conquered from primitive countries (that weren't colonized, so including provinces settled by native tribes) cause overextension as normal.

Colonial subject nations

Main articles: Colonial nation, Trade company

Colonial nations and trade companies are specialized subject nations that can be formed via colonization (or conquest of the appropriate regions). Understanding both types of colonial subject nations is key to benefitting from the colonization process.

Using colonial nations or trade companies to produce and control trade value in nodes, as well as utilizing them to gain free merchants or military control of overseas territories, are some of the benefits these subjects can provide a parent nation.

With Wealth of Nations, a country gains +1 merchant for each trade company that controls the majority (>51%) of the provincial trade power in that region. (Non-trade company provinces in that region and sources of trade power other than directly from the provinces are not considered.)

Apart from the 50% trade power they normally transfer to their overlord, each colonial nation comprising 10 or more provinces will provide their overlord with +5% global trade power, an extra merchant, and variable amount of naval force limit, land force limit, sailors and manpower which depend on the size of the colonial nation and its designation. With the Leviathan DLC, the subject relationship can be modified further to give different benefits to the colonial nation or its overlord.

Accordingly large colonial nation subjects add significant military power to their overlord and are therefore a potent weapon especially for smaller nations assuming such overlords maintain a sufficiently large fleet to control their subjects and manage their liberty desire.

Seven Cities of Gold and the Fountain of Youth

Main article: Seven Cities events

With El Dorado, using a conquistador to explore terra incognita in a colonial region will sometimes trigger events based upon the search (and sometimes discovery!) of mythical locations in the New World. These events can provide monarch points, ducats or prestige and add flavor and occasionally material benefit to the exploration of the New World.

Discovering a city gives a permanent province modifier with various local effects (except Cibola which gives +5 Yearly tax income), 800 ducats ( 400 ducats for the medium outcome) and adds 4 base tax, 4 base production and 4 base manpower to the province ( 2, 2, 2 for the medium outcome).

Siberian frontier

Siberian frontier is a unique colonization system primarily for Russia to model its rapid expansion into Siberia. Once a united Russia unlocks its second national idea, it may establish a Siberian Frontier colony in any empty province with a direct land connection to its capital passing through non-colony provinces. Establishing a frontier costs 20 diplomatic power. The new colony will start with 5 settlers instead of the usual 10. Frontier provinces do not count towards the colony limit or require monthly maintenance. They grow at a varying rate of +5 – 15 settlers per month, but since many Siberian Frontiers can be established at the same time, Russia can reach the Pacific Ocean fairly quickly.

A few missions give other countries individual colonies that grow using the same system. They will still be labeled as "Siberian frontiers" even if they are in, e.g., Africa.

Expel minorities

A nation can choose to expel minorities from a home province to a colony in the new world. This will give the colony the home province's culture and religion. In addition the colony will gain bonus development and an increased settler chance based on the development of the home province. Note, however, that the home province will lose the same amount of development given as bonus to the colony.

Minorities cannot be expelled from a province with separatism. Expelling a minority removes the Religious Zeal of the home province and adds a province modifier for 20 years, which increases the local missionary strength by +5% and decreases the local culture cost by −25%. Once expulsion has begun, the colonist cannot be recalled until the colony is finished, though the colony can be abandoned instead.

Maintenance cost for these colonies can be reduced by following:

	Conditions
−25%	with French mission “Dragonnades”
−100%	with government reform Exile Colonial Companies

See also

• Colonization strategies

Footnotes

Mechanics

Customization

Nation designer • Random New World

Ages and Institutions

Ages • Institutions

Innovativeness and Technology

Innovativeness • Technology

Defense

Fort • Zone of control