The topic of the recent Victoria 3 Dev Diary is Migration, meaning the movement of Pops between states, what role it plays in Victoria 3, and how it functions mechanically. One type of Migration is Intra-Market Migration.
Intra-Market Migration is the movement of Pops between two States that are part of the same Market. Barring certain exceptions, such as slaves not being able to migrate, as covered in the previous Dev Diary, Pops are generally always able to move between States in the Market, though the number of individuals that are able to change their homes on a weekly basis varies based on factors such as the local Infrastructure and Market Access in the two States.
Which Pops migrate from and to what States depends on the Migration Attraction of each State. Migration Attraction is a value that is based on the average Standard of Living in the state and modified by various factors such as over/underpopulation, unemployment/available jobs, and so on. It is possible for a country to directly encourage.
Migration to a specific state through the ‘Greener Grass Campaign’ Decree, at the cost of some Authority. In general, Pops will move from States with a low standard of living and a lack of employment opportunities to states with a high standard of living and jobs to offer. States with a low population compared to the amount of available land are especially attractive to economic immigrants.
Discrimination, too, plays a role in migration. Pops that are being discriminated against in a particular State, and have the opportunity to migrate to another State in that market where they would not be discriminated against will take that opportunity in greater numbers, provided of course that there is an underlying economic reason for them to want to move there in the first place. After all, while enjoying voting rights is certainly nice, putting food on the table is higher on the agenda for most Pops.
Discrimination can also have the opposite effect: Pops that are already enjoying full citizen rights are generally going to need to be in pretty dire economic straits to consider moving somewhere where those rights are going to be taken away, and in the case of a Pop that is going to be discriminated against no matter where they go in the Market, they tend to stick to their cultural Homelands.