I think the "We yearn to join our motherland" might be bugged. In my last game, I captured one city from the barbs and even after all the map was discovered and all the barb cities destroyed, the citizens were still complaining.
Same for another city that I took from the Japanese. 1000 years after the japanese civ was anihilated, I still had that message.
Same for another city that I took from the Japanese. 1000 years after the japanese civ was anihilated, I still had that message.