Does anyone know to unlock the Foreign Customs civic? I've been trying to unlock this civic for the past week but I just can't figure out how to activate it. So far I've tried

1. Letting one/some/all of my cities fall under the influence of another Empire
2. Controlling territory in two different spheres of influence at the same time
3. Capturing another Empire's city through war while it was under their sphere of influence prior to war
4. Capturing another Empire's city with a cultural wonder in it through war
5. Capturing another Empire's city after having enacted Multiculturalism for the Cultural Blessings civic

I don't know what is the trigger but from my experience it trigger early ( ancient era or classical era )

Gwanelle wrote:

I don't know what is the trigger but from my experience it trigger early ( ancient era or classical era )

Do you play aggressively early game? I'm pretty sure unlocking the civic has something to do with conquering a city, I just can't figure out what specific conditions need to be met surrounding that.