Southern and evangelical Americans are not an ethnic group. They are simply a category of mainstream Americans with some weird ideas.
The worth of cultural patterns may be "an opinion", but I maintain that female mutilation is evil, as is sati, slavery, racial discrimination, honour killings, murdering female babies for being female, genocide and many other cultural phenomena. One must draw the line against cultural relativism somewhere, without bothering too much about semantic or philosophical quibbling. The same goes for terminology: I was not engaged in discussing whether one should talk about ethnologists, human anthropologists or culture studies.
On topic: How about a Great Barbarian who suddenly appears and turns some of your citizens into barbarians who have to be suppressed or re-assimilated? Or the possible appearance, after the discovery of Scientific Method, of creationists who drag down research for a number of turns? "In the city of Bombay, a group of religious fanatics boycott the schools for not teaching the tenets of their religion as science, which has drastically hurt education and research there. Pay XX gold, or the aberration my spread to other cities."