The Cathedral produces three content faces, making three unhappy citizens content. You must have a Temple in the city in order to build a Cathedral.
Throughout the Dark Ages that followed the fall of the Roman Empire, the Christian Church was a major influence in the revival of European civilization. In recognition of the expanding influence of the church, great cathedrals were built in the largest towns and cities, to act as centers of religious study and worship. In addition to their religious significance, cathedrals acted as the center of social and cultural activity in the town. They brought great pride, stability, and tradition to the citizens of the community.