The population of each city is used to determine city upgrades and the number of units the city can support. Every city has a set of population bars under its name representing how much population the city needs to upgrade. The amount of population required to upgrade a city is one more than the city's current level, e.g., it takes two population to upgrade a city from level 1 to level 2. How much population a city currently has is represented by the number of filled-in (blue) population bars.
Population can be gained by harvesting resources, constructing buildings, or forming city connections. If a building is destroyed or a city connection is lost, then the population it produces will also be lost. A city may have negative population, shown as red population bars. (This typically occurs to a former capital that has lost the population produced from city connections.) Each negative population decreases the income the city produces by one star per turn up to the point where the city no longer produces any income. However, negative population does not impact the number of units a city can support.
It is theoretically possible (barring technical limitations) for tribes other than ∑∫ỹriȱŋ to produce infinite population using captured Sanctuaries, which attract wild animals that can then be hunted. However, this produces population too slowly to be practically useful.
|Item||Population||Cost (stars)||Population per star||Unlocked by|
|Sawmill||1 per friendly adjacent Lumber Hut||5||Varies||Mathematics|
|Windmill||1 per friendly adjacent Farm||5||Varies||Construction|
|Forge||2 per friendly adjacent Mine||5||Varies||Smithery|
|City connection||1 in both the capital and connected city||Varies||Varies||Roads[note 1]|