There are two kinds of Assimilation in the game. Cultural assimilation where POPs of non-accepted culture will turn into POPs of the primary culture, and religious conversion where POPs not following the state religion will convert to the state religion. Both happens over time automatically.
Cultural Assimilation and Religious Conversion are similar to Promotion and Demotion and Immigration, except that they do not have a direction roll. Instead, they automatically assimilate or convert to the national primary culture or national religion if POPs of those types exist in the province. For example, Italian POPs will assimilate to the Yankee culture in New York City, but not in Los Angeles (until some Yankees migrate there at least).
Cultural Assimilation
Cultural Assimilation is the phenomenon that people of not-accepted cultures will turn into the primary culture of the nation. (For example, German pops living in Denmark will slowly turn into Danes)
The formula for calculating the number of people in a pop to assimilate each month is the following:
Number to Assimilate = Pop Size x Base Assimilation Rate x (1 + Continent Modifier) x Total Assimilation Factor (as shown in game) x 100
where:
Base Assimilation Rate = 0.40% per month (vanilla) Continent Modifier = -0.25 (Europe); -0.5 (Asia); -0.25 (Africa); 0.5 (Americas and Oceania)
| Modifier | Value | Factor | Total |
|---|---|---|---|
| Literacy ≥ | 60% | +0.10% | +0.10% |
| 70% | +0.10% | +0.20% | |
| 80% | +0.10% | +0.30% | |
| Has Cultural Core | -20.00% | ||
| Is NOT Accepted Culture AND Continent is North America OR South America OR Oceania |
+10.00% | ||
| Luxury Needs ≥ | 10% | +0.20% | +0.20% |
| 30% | +0.20% | +0.40% | |
| 50% | +0.20% | +0.60% | |
| 70% | +0.20% | +0.80% | |
| 90% | +0.20% | +1.00% | |
| Militancy ≥ | 7 | -0.20% | -0.20% |
| 8 | -0.20% | -0.40% | |
| 9 | -0.20% | -0.60% | |
| Is Accepted Culture | -1.00% | ||
| Unemployment < | 10% | +0.05% | +0.05% |
| 5% | +0.05% | +0.10% |
Religious Conversion
Similarly, the formula for calculating the number of people in a pop to convert each month is the following:
Number to Convert = Pop Size x Base Conversion Rate x Total Conversion Factor (as shown in game) x 100
where:
Base Conversion Rate = 1% per month (vanilla)
| Modifier | Value | Factor | Total |
|---|---|---|---|
| Literacy ≥ | 40% | +0.05% | +0.05% |
| 50% | +0.05% | +0.10% | |
| 60% | +0.05% | +0.15% | |
| Luxury Needs < | 90% | +0.20% | +0.20% |
| 70% | +0.20% | +0.40% | |
| 50% | +0.20% | +0.60% | |
| Life Needs < | 90% | +0.05% | +0.05% |
| 80% | +0.05% | +0.10% | |
| 70% | +0.05% | +0.15% | |
| NOT National Culture | +0.15% | ||
| Unemployment > | 10% | +0.05% | +0.05% |
| 20% | +0.05% | +0.10% | |
| 30% | +0.05% | +0.15% |