How many turns for loyalist sentiment to subside?

[anweRU]

How many turns does it take for a city's loyalist sentiment for prior owner to reduce to 0? Is it 1 point per turn, or some other rate?

[Fiddling_nero]

Depends on your actions in the settlement. The resentment may last indefinitely unless you do something to endear the population to your rule. Tax exemption is perhaps the most consistent way to bring new settlements into the fold, along with a garrison. (I build up some militia for this purpose so I may have my crack troops available for bigger and better things.)
Note: the capitols of major powers take considerably longer to quell unrest.

[Squints]

Doesn't recruiting from the city in question make them angrier, though? Or is it ultimately offset by the troops you recruit?

[A Very Super Market]

Why would it make them angrier?

There are significant amounts of population that don't care, because the most fervent guys will killed as the mob (He-he-he).