Ok so if interstate relations dont come into the equation then it would be based on:
- Religious tolerance within State A
- Non-accepted culture within State A (maybe you disagree with this but I would imagine that minority cultures would be more likely to emigrate)
- QFTNW/Land of Opportunity NI for state B
- Maybe decreased MTTH if State B has higher tolerance
- Would this be strictly a European scope? If a Muslim country colonised could Muslims living under Christian states migrate?