The population of the world is represented by individual "population units", or “pop” for short. Each population unit has a unique ID in the save game file.
A pop belongs to one of the four available social classes. It is the social class which determines what a pop produces!
- Citizens – generate research points and commerce income
- Freemen – generate manpower and tax income
- Tribesmen – generate manpower and tax income
- Slaves – generate tax income; additionally produce surplus goods
Population cannot be pro- or demoted by the player! Instead the population will slowly approach the "desired ratio" for the territory, which varries by the Nation, Buildings and Civilisation and other factors. This ratio and the rate of change can be affected by player choices, however.
There are a few effects that can directly change Social Class:
- When a City is occupied, there is a chance that Citizens will be demoted ⇒ Freemen and Freemen ⇒ Slaves.
- when any territory (including a city) is occupied), some of these generated slaves will be abducted (teleported) to a provincial or state capital of the sacking nation for no cost.
Each Citizen Pop at 100% Happiness produces per month:
- 0.25 Research Point
- 0.01 Commerce Value
- Food Consumption: 0.3
- Base Happiness: 20%
Citizens only have a relevant desired Ratio in cities and metropolises. Their happiness is heavily affected by Civilisation level, and is otherwise rather hard to manage. Both their Ratio and happiness can be buffed via the Library Building. They are the only source of Research output (wich is buffed primarily by the Academy) and thus a must have even for Tribal Nations.
Each Freeman Pop at 100% Happiness produces per month:
- 0.005 Base Tax
- 5 Manpower
- Food Consumption: 0.2
- Base Happiness: 25%
Freemen can be found in cities. Unless there are barracks, they are usually not found in Settlements. They are slightly easier to maintain then Citizens, but about equally affected by Civilisation Level. They produce relevant amounts of Manpower, so their usefullness is highly situational.
Each Tribesmen Pop at 100% Happiness produces per month:
- 0.015 Base Tax
- 3 Manpower
- Food Consumption: 0.2
- Base Happiness: 80%
Tribesmen are easy to keep happy, but receive a penalty for Civilisation level. Their values are relatively low - being beaten in income by the Citizens Commerce and Manpower by the Freemen - however actually getting those outputs is easier due to high base happiness.
For Tribal nations, they make up 50% of the Settlement Population, limiting the space available for slaves and thus tradegoods and tax production. In cities they are less common, but still have a noticeable ratio.
For Non-Tribal nations they are generally of little use, besides as population that can be promoted or demoted to something more useful. For these nations, they have a desired ratio of 0% everywhere.
Each Slave Pop at 100% Happiness produces per month:
- 0.02 Base Tax
- Base Happiness: 90%
- Food Consumption: 0.1
- (semi-hidden) Extra Tradegoods
Slaves are the backbone of every economy during the time frame of the game. There is not a single nation and a single territory that does not have, want or need slaves. They are mostly found in settlements, where they make up 100% (Civilised) or 50% (Tribal) population. But they are also found in cities. Their high base happiness can be misleading as especially those captured in war tend to be of the wrong culture and religion.
While they produce more tax than any other Population type, their main purpose seem to be to produce additional Trade goods. Every 15 slaves (situational modifiers can lower that) the territory will produce an additional tradegood.
A territory with 10 or more slaves with less than 50% happiness may spawn a slave uprising.
Depending on their type, pops produce gold, manpower, and research points, and are the main (or only) source of these resources in the game. In addition to the output modifiers for each specific resource, the population output modifier will also increase the production of all resources produced by pops, and is in general one of the most powerful economic modifiers. Pop output can also be affected on a class-specific basis with the local/national citizen output, local/national freeman output, local/national tribesman output, and local/national slave output modifiers.
Output modifiers are given from a large variety of sources, such as buildings, deities and omens, laws and government forms, inventions, and more. Notably, population output is also significantly decreased by law pop happiness and high local unrest, which means that keeping pops happy and content is important for maintaining a strong economy.
- Output: a pop's output is scaled to its current happiness. For instance, a freeman pop at 50% happiness generates only 5 Manpower instead of 10.
- Unrest: any pop with happiness less than 50% generates unrest to the city it currently resides in. A city with high enough unrest triggers a rebellion.
- City's civilization value
- Trade goods
- Religions and cultures different to the state's; such pops are also affected by assimilation and/or conversion (where applicable)
In general, there are 3 different sets of modifiers that will each affect a different set of pops:
- Pop type modifiers ( local/national citizen happiness, local/national freeman happiness, local/national tribesman happiness, and local/national slave happiness modifiers)
- Culture modifiers ( primary culture happiness, wrong culture happiness, and wrong culture-group happiness modifiers)
- Religion modifiers ( state religion happiness and state religion pantheon deity modifiers)
Population culture and religion
As each state has its own State Culture and Religion, so does each pop unit have its own as well. When a pop's religion and/or culture differs from the state in which they resides, that pop's happiness is affected (usually negatively). Ensuring that a majority of the state's pops are of the state's Culture and Religion is a crucial step in securing the stability and prosperity of the state.
Population of each social class can change through several means: Growth/Death and Conquest.
The base rate of population growth in each city in the game is 0.04%/month. When this number reaches 100% a new pop of that type is born in that city. There are many modifiers to this value. The population growth in a city is altered by factors such as terrain type, Stability, and availability of trade goods. Note that all bonuses are additive, therefore population growth omen power may multiple the growth rate in every city you have.
- Religion: Hellenic Diety of Fertility Demeter gives a passive effect of National Population Growth: +0.1%
- Being in peace gives 0.04%/month.
- Above 50 stability gives progressively more growth rate. Having 100 stability gives 0.5%/month, while having 50 stability or lower gives 0%/month.
- Several laws give various, but very low rate of growth, typically between 0.01%/month and 0.05%/month.
- Every 12 months of stored food applies a bonus of 0.05% population growth up to a maximum of 0.5%. Provincial food storage capacity is increased by granaries and salt surplus.
- Monarchy Taxation Law: Infrastructure Policy gives National Population Growth: +0.1% and increases governor loyalty by +10 while decreasing general loyalty by -10.
If aiming to boost your population size, aim for stability (while it gives the highest potential growth rate, it is the most costly to keep high), and stored food. Having multiple of the trade goods or other modifiers have an extremely low benefit.
When a new pop starts to grow, its social class is determined by chance, from the available pops already living in the city. Its culture and religion is also determined upon it starting to grow. They are also randomly selected from the religion and culture already present in the city. For example if a city has no Tribesman then it will never start to grow. It is possible to promote all of your (for example) tribesman into freeman, and still end up with one, if it was already growing when you have promoted the already grown ones.
Population growth in a city can also become negative (by modifiers). If this happens, the growing pop will shrink instead. If there is no growing pop, an existing pop will be chosen (at random) and a progress bar toward 0 will start. If it reaches 0%, that pop will die.
Population is also gained through warfare. As cities are sacked, POWs are taken to the state capital or to the provincial capitals as slaves. It should be noted, that pops within the newly conquered city may be demoted:
- Citizen ⇒ Freemen (50% chance)
- Freemen ⇒ Slaves (50% chance)
Tribesmen and Slaves never change their social class upon conquest.
- Enslavement (From either war occupation or slave raiding. Slaves are heavily weighted to go to national or province capitals.)
- Scripted Events
- Manual movements of slaves (but not citizens or freemen) by spending gold
- Tribal nations can move tribesman similar to slaves.
- Tribal nations can also trigger a "tribal migration" via the Government Interface
A slave pop can be moved from a territory to any territory in the same province or an adjacent territory.
Moving slaves costs a base of 5 gold.
- Capital surplus of vegetables lowers cost by 1 gold.
- Exporting vegetables lowers cost by 0.5 gold.
- Main article: Colonization
Pops are used to colonize unowned territories.
At least 10 pops of your country's primary culture are needed in any neighboring province or up to 2 sea tiles away. Colonizing has a two year cooldown from the colonizing territory.
Each territory has a base population capacity which is modified by a number of population capacity modifiers from terrain, technology, resources and events. These modifiers also apply on aqueducts and other things that may increase the base pop cap. Knowing which territories are good for population growth is essential in city placement and economic planning.
Some common modifiers include:
- Farmland: 50%
- Desert: -30%
- Mountains: -20%
- Jungle: -20%
- Forest: -10%
- Marsh: -10%
- Coastal: 10%
- Coastal port: 25%
- Salt (in province): 10% (not stackable)
- Horses (surplus): 5% (stackable)
- Warm climate: 40%
- Temperate climate: 10%
- Frigid climate: -20%
- Alpine climate: -30%
- Arid climate : -15%
- Nearby river: 20%
- Adjacent to major river: 50%
- Capital territory: 35%
- Province capital: 25%
- Civic advances: 2% per level.
- Number of trade routes in province: 2% per import and export route.
- Settlements: in monarchies and republics the base ratio is 100% slaves, in tribal nations is 50% tribesmen and 50% slaves. This can be modified building Barracks that increase the desired ratio of freemen in settlements by +75%.
- Cities: the base ratio in monarchies is 35% citizens, 35% freemen, 0% tribesmen, 30% slaves; in republics is 34% citizens, 39% freemen, 0% tribesmen, 27% slaves; in tribal nations is 33% citizens, 33% freemen, 4% tribesmen, 30% slaves.
These ratios can be modified by the local/national citizen ratio, local/national freeman ratio, local/national tribesman ratio, and local/national slave ratio modifiers, most prominently available from various laws and buildings (e.g. Libraries increase desired ratio of citizen, Mills increase ratio of slaves). The player can increase migration of non slaves pops from settlements to cities in order to promote more pops to citizen status. This is generally recommended because citizens are the only source of research and are needed to keep up in technologies.
Every social class has a promotion speed value:
- Slave promoting: +4
- Tribesman promoting: +0.4
- Freeman promoting: +4
this can be directly modified building Academies (+0.5 each), using the Social mobility edict in the province (+% based on governor finesse), enacting the second Land reform law in republics (+6).
To the values listed above are applied different modifiers. Some common modifiers include:
- Settlement: -25%
- Capital territory: 25%
- Province capital: 10%
- Coastal port: 10%
- Unrest: -1% every 0.1 unrest
- Number of Trade route: 5% every active trade route
- Road Network in territory: 2.5% for each road entering the territory
- Total population: 2.5% every pop living in the territory
- Positive centralization: 2.5% at 100 centralization
- Civic invention Granted Manumission at tech 10: 10%
- Civic invention Gradated Citizenship at tech 17: 20%