avatar the last airbender AU

There were 4 clans in the world. The lowest being the Earth Tribe. They were slaves, workers of the caves and mines. Above them came the Water Tribe, they were the gypsies that danced in carnivals. Next is the Fire Tribe, they were the nobility, the rulers of the land. Finally, the Air Tribe. They were the gods who never came down from their temples in the sky.