According to a list I saw, the towns with a 15% unrest penalty are:
Bordesholm, Domus Dulcis Domus, Vicus Gothi, Batavodorum, Damme, Vicus Marcomanni, Tanais, Mogontiacum, Segestica, Tylis, Asturica, Salona, Numantia, Osca, Scallabis, Carthago Nova, Corduba, Palma, Croton, Dumatha, Bostra, Dimmidi, Petra and Nepte.
Those with a 30% penalty are:
Themiskyra, Deva, Londinium, Tarsus and Jerusalem.
This doesn't apply to the faction originally owning it. IMHO this is wrong in the case of Jerusalem, which was ALWAYS rebelling against foreign oppressors.
I suspect it's intended to make life harder for the Roman factions, as most of these places will already have considerable cultural/distance to capital penalties.
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