Religion

Each City and character will follow their own Religion. When enough characters in a Family convert to the Nation's religion the Nation will receive additional benefits. Cities that follow a Religion will gain a yield bonus of 2 Culture. If the Opinion of its Religion of the Nation is Pleased or Friendly the city will gain Happiness. However if the Opinion of its Religion of the Nation is Upset, Angry, or Furious, the City will gain Discontent. The city where a Religion is first founded will be its Holy City and gain a yield bonus of 2 Civics.

There are two types of religions in Old World: Pagan Religions and World Religions. Pagan Religions are unique to each Nation and founded once the Nation completes its first Shrine improvement. Pagan Religions cannot spread, do not have Disciples and Theologies and can only be adopted as State Religion with the Divine Rule law.

World Religions

World Religions can be founded once certain requirements are met, or when a Family Seat is founded for a Clerics family. They have Disciples and Theologies and can always be adopted as State Religions. World Religions have a small chance of spreading to a City or Tribe each year. The chance increases if the City or Tribe is closer to the Religion's Holy City and decreases if the City or Tribe already has a Religion.

When a World Religion is founded, it founder will receive the option to gain 50 Civics, make a donation and gain 40 Opinion with the Religion for 40 years, or gain 2 Legitimacy and lose 40 Opinion with the Religion for 40 years.

World Religion	Founding Requirements	Disciple Appearance	Monastery Appearance	Temple Appearance	Cathedral Appearance	Holy Site Appearance
Zoroastrianism	2 Acolyte specialists
Judaism	Labor Force technology 2 Rancher specialists
Christianity	Metaphysics technology 2 Cities in the world that follow Judaism 1 Owned City that follows Judaism 12 Citizens
Manichaeism	Monasticism technology 2 Cities in the world that follow Christianity 2 Cities in the world that follow Zoroastrianism

State Religion

A Nation may adopt a Religion as its State Religion at the cost of 400 Civics. Adopting a Religion as State Religion has the following effects:

• All cities that follow the Religion gain 1 Happiness each year
• All cities that follow the Religion lose 1 Civics each year
• If the Nation Leader doesn't follow the State Religion they will gain the choice to convert or lose 40 Opinion with the Religion for 40 years
• Disciples can establish Theologies

Theology

Theologies can only be created by Nations that have a World Religion as their State Religion and require the use of a Disciple. Theologies will grant a city yield bonus to all Nations that have the Religion as its State Religion and increases the chance for the Religion to spread by 5%. Each World Religion may have up to 3 Theologies.

Theology	Yearly Yield	Religion Opinion	Required Technology	Civics Cost
Legalism	-10% Maintenance [Each Cities] +2 Civics per Monastery +5% Spread Chance (per year)	+20 Centralization law	None	200
Mythology	+2 Culture per Shrine +4 Culture per Monastery	+20 Polytheism law	None	200
Veneration	+20 Money per Monastery -5% Rebels Chance [Each City] +10% Spread Chance (per year)	+20 Iconography law	None	200
Dualism	+1 Science per year, per Religion [Each City] +1 Happiness per Temple +5% Spread Chance (per year)	+20 Tolerance law	Rhetoric	400
Gnosticism	+2 Civics with Archive[Each City] +1 Science per Urban Specialist +5% Spread Chance (per year)	+20 Monotheism law	Drama	400
Revelation	+0.5 Orders with Temple+20% Spread Chance (per year)	+20 Orthodoxy law	Labor Force	400
Enlightenment	+3 Happiness per Elder Monk +1 Growth per Citizen per Cathedral +5% Spread Chance (per year)	+20 Philosophy law	Forestry	600
Redemption	+20% Harbor Yield +20% Hamlet Yield +20% Mine Yield per Cathedral +20% Quarry Yield per Cathedral +20% Lumbermill Yield per Cathedral +5% Spread Chance (per year)	+20 Pilgrimage law	Metaphysics	600

Dissent

If the The Sacred and The Profane DLC is installed, Cities that follow a World Religion whose Opinion is Upset, Angry or Furious can cause Dissent, which has a 5% chance each year to spawn Rebels. Dissent can be removed either by using the Quell Dissent action or the Suppress Dissent project.