Population is how many people you have in a city. It consists of Labor Force who produces resources, Construction Workers who build and upgrade your buildings, and Idle People who can be trained into army units in Barrack. It is affected by three factors: Population Cap, Tax Rate and Happiness.
What Affects PopulationEdit
Population is equal to the Population Cap given by your Houses times Happiness. Happiness is 100 - Tax Rate. For example, if your Population Cap is 50,000, and Tax Rate is set to 20%, normally you should have 100-20= 80 Happiness. 50,000 x 80% is equal to 40,000. However, if you lose a battle, there will be a decrease in Population due to battle toll.
How to Boost PopulationEdit
There are several ways to increase the population either steadily or swiftly.
Build and Upgrade HousesEdit
Expanding the capacity of your Houses increases the Population Cap of your city, which greatly affects your Population.
Lower Tax RateEdit
To have lower Tax Rate, you will have high Happiness, thus increasing your Population.
Use Immigrant OrderEdit
Immigrant Order will attract vagabonds to settle down at your city. It increases your city Population by 20% of your Population Cap (at least 100). It cannot be used when your city population exceeds your Population Cap.
Raising Population is one of the Goodwills you can perform in the City Hall. It will increase population by 5% of your Population Cap but the total number will not exceed Population Cap. The Grain it takes is 5 times of your Population Cap.