Ethnicity...

[Redrum]

Ethnicity should also play a part in the population besides religion and it would add a little more of a challenge to control your people. Ethnicities would be spread by building schools or cultural center buildings, it could also be spread a little by having free trade agreements between 2 bordering territories or if you conquered a territory it would open up the border fully bringing more immigrants than it would have in the hands of your opponent.

To decrease an ethnicity you would have options to let the course of building certain buildings or immigration take place or expel or exterminate certain ethnicity to significantly decrease that population which was done often by some during those times. Trying to expel a certain ethnicity would encourage more rebellions in that region or a massive revolt in that particular region, so you would need to ensure you have a big army in that region before you do so.

Also having a certain ethnicity in your region would help you recruit a unit related to that particular ethnicity.

What yall think?

[megalitho]

If you mean culture: That is a good idea, but i don´t know how it can be technically realized. The team of Paeninsula Italica II has a system that shows the culture of the population in your settlement, but this system replaces the religion system. The religion system is the center of Broken Crescent and the team will bring more different religions into future versions (what makes the mod also more challenging), so i doubt, that this system will be replaced. If you know another way: Please let me know [Edit:]If I remember correctly RTW had a system that allows the player to enslave the population of a captured settlement. The slaves (and their culture) were allocated to all the other settlements in the empire and a colonial boom began in the new city that increases rapidly the amount of friendly culture in the population.

If you really mean ethnicity: Ethnically assimilation is a process that is way slower than religious or cultural assimilation. I don´t want to bring examples for that, but the Middle East of today is full of ethnically unrest - not only religious. I can´t advise to bring a system like that into the mod, because it will completely destroy the gameplay.

[wudang_clown]

I think the simplest and most obvious way of representing ethnicities is to do it by properly presenting units (names and descriptions), and creating special structures (buildings) and coded revolts.

Cultures feature isn't good for that, are there can only be 7 cultures.