A land being plunged into chaotic energies, wild superstition, massive prejudices and distrust. More of a campaign setting than anything else.
This is more of a concept applied to a particular setting than the setting itself, bear this in mind.
A town has a festival every year in the dead of winter. The festival of birds. The towns folk dress in feathery robes and beaked masks and dance and frolic in the belief that the changes of the seasons are controlled by the presence of birds. According to tradition, the festival tricks Spring into coming early because the birds have returned.