Let me start by saying that I believe the idea fits within the theme of Gathering Storm, tackling modern challenges, and being within the cadre of existing game mechanics.
Kicking it off with Ethnicity!
Every citizen born would have an ethnicity: that of the nation it was born under. So would Spies, Settlers and Traders.
Whenever a city changes owner, the current citizens' ethnicity remains the same, but subsequent new citizens are of the new/current owner's ethnicity.
Every era, if a city is multiethnic, at least one citizen converts to the owner's ethnicity. More, depending on happiness level (Content or less = 1, Happy = 2, Ecstatic = 3), provided that loyalty is at 100%, and that the city is not being occupied (Aka, has been ceded following a peace treaty if it was conquered). This may only occur once per era.
Effects: Spies and Traders are more effective the higher their ethnicity is represented in the city they operate in.
Once all of a conquered city's citizens have assimilated to their new overlords' ethnicity, the city can no longer be liberated, it is considered to be fully loyal. For every 20% of the city's population that is not of the owner's ethnicity, loyalty takes a -1 counter.
Upon declaring war, there is a chance that a multiethnic city will spawn rebels, if the enemy's ethnicity is represented in the city. That chance scales with the proportion of that representation.
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On to Migration!
This feature would see the creation of two new units: Refugees, and Migrants. Both would act like a one-way trade route, could be plundered or captured. Plundering would cause a severe diplomatic penalty for eliminating the civilian unit, and capturing would carry a lesser but still major diplomatic penalty, though allowing you to boost your own population.
Migrants would be of the ethnicity of your choice, provided there is a citizen of that ethnicity in the origin city, while refugees would first be of a random foreign ethnicity present in the origin city
Migrants would occur on command while Refugees would depart automatically, in the event of conquest, natural disaster, or severe unhappiness.
A Migrant or Refugee unit represents one citizen of its origin city moving to a different destination city.
Refugee units would algorithmically pick their destination based on the destination's ethnic composition, happiness, and proximity.
Migrant units would only be created by purchasing them, much like you would any other unit, then sending them to a city using a tab in the trader window.
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What's the point?
These ideas use existing mechanics to allow for population transfers, a very current yet timeless issue.
Refugees would be useful to salvage something out of city loss for defenders, also encouraging defenders to actually fight to keep supply lines open, allowing the refugees to reach better protected cities, minimizing population loss. They would also make it more worthwhile for attackers to effectively besiege a city, preventing refugees' escape.
Migrants would be a tremendously useful - though expensive - tool, say, to put to good use all those citizens born in your city surrounded by farmland, by sending them to your city surrounded by mines. It would also help in mitigating the undesirable effects of ruling over foreign-built cities, by dispersing the local ethnicity throughout your empire.
Whereas Ethnicity adds more flair to the idea of an empire, which have historically been very multicultural constructs, adding realism to the game, and an additional layer of uniqueness to your civilization, which you can play with as you see fit.
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Complementary points
-I would add that it would be better if undefended and unprotected (aka, non-garrisoned, non-walled) cities be immediately surrendered when stepped on by enemy troops, as if the city had capitulated. This would allow players to preserve their cities before retaking them. Paris in WW2 would be a good example of that. Population loss would still occur, but only as a result of refugees escaping the city. As well, when combat does concur in a city, then civilian casualties would occur, but in a lesser amount than it does currently, as this reduction would be offset by Refugees also causing a population loss.
-Additionally, it should be possible to grant cities "Autonomy", allowing them to determine their production queue and priorities independently of the owner's wishes, but also mitigating the negative effects of multiethnicity. Autonomous cities should favour city center buildings, food, and entertainment.
-And I wish to reiterate that all those ideas are based on existing mechanics, and fit the theme of Gathering Storm, especially as we saw in Canada's (a very multicultural country, mind you) gameplay review today, when they showed us that you could pass the "Migration Treaty" proposal in the World Congress.
Kicking it off with Ethnicity!
Every citizen born would have an ethnicity: that of the nation it was born under. So would Spies, Settlers and Traders.
Whenever a city changes owner, the current citizens' ethnicity remains the same, but subsequent new citizens are of the new/current owner's ethnicity.
Every era, if a city is multiethnic, at least one citizen converts to the owner's ethnicity. More, depending on happiness level (Content or less = 1, Happy = 2, Ecstatic = 3), provided that loyalty is at 100%, and that the city is not being occupied (Aka, has been ceded following a peace treaty if it was conquered). This may only occur once per era.
Effects: Spies and Traders are more effective the higher their ethnicity is represented in the city they operate in.
Once all of a conquered city's citizens have assimilated to their new overlords' ethnicity, the city can no longer be liberated, it is considered to be fully loyal. For every 20% of the city's population that is not of the owner's ethnicity, loyalty takes a -1 counter.
Upon declaring war, there is a chance that a multiethnic city will spawn rebels, if the enemy's ethnicity is represented in the city. That chance scales with the proportion of that representation.
---------------------------------
On to Migration!
This feature would see the creation of two new units: Refugees, and Migrants. Both would act like a one-way trade route, could be plundered or captured. Plundering would cause a severe diplomatic penalty for eliminating the civilian unit, and capturing would carry a lesser but still major diplomatic penalty, though allowing you to boost your own population.
Migrants would be of the ethnicity of your choice, provided there is a citizen of that ethnicity in the origin city, while refugees would first be of a random foreign ethnicity present in the origin city
Migrants would occur on command while Refugees would depart automatically, in the event of conquest, natural disaster, or severe unhappiness.
A Migrant or Refugee unit represents one citizen of its origin city moving to a different destination city.
Refugee units would algorithmically pick their destination based on the destination's ethnic composition, happiness, and proximity.
Migrant units would only be created by purchasing them, much like you would any other unit, then sending them to a city using a tab in the trader window.
--------------------------------
What's the point?
These ideas use existing mechanics to allow for population transfers, a very current yet timeless issue.
Refugees would be useful to salvage something out of city loss for defenders, also encouraging defenders to actually fight to keep supply lines open, allowing the refugees to reach better protected cities, minimizing population loss. They would also make it more worthwhile for attackers to effectively besiege a city, preventing refugees' escape.
Migrants would be a tremendously useful - though expensive - tool, say, to put to good use all those citizens born in your city surrounded by farmland, by sending them to your city surrounded by mines. It would also help in mitigating the undesirable effects of ruling over foreign-built cities, by dispersing the local ethnicity throughout your empire.
Whereas Ethnicity adds more flair to the idea of an empire, which have historically been very multicultural constructs, adding realism to the game, and an additional layer of uniqueness to your civilization, which you can play with as you see fit.
-------------------------------
Complementary points
-I would add that it would be better if undefended and unprotected (aka, non-garrisoned, non-walled) cities be immediately surrendered when stepped on by enemy troops, as if the city had capitulated. This would allow players to preserve their cities before retaking them. Paris in WW2 would be a good example of that. Population loss would still occur, but only as a result of refugees escaping the city. As well, when combat does concur in a city, then civilian casualties would occur, but in a lesser amount than it does currently, as this reduction would be offset by Refugees also causing a population loss.
-Additionally, it should be possible to grant cities "Autonomy", allowing them to determine their production queue and priorities independently of the owner's wishes, but also mitigating the negative effects of multiethnicity. Autonomous cities should favour city center buildings, food, and entertainment.
-And I wish to reiterate that all those ideas are based on existing mechanics, and fit the theme of Gathering Storm, especially as we saw in Canada's (a very multicultural country, mind you) gameplay review today, when they showed us that you could pass the "Migration Treaty" proposal in the World Congress.
