Chaucer's narrative technique in "The Nun's Priest's Tale.

It is an animal fable. In this story the animals demonstrate human characteristics. The fox, for example, shows hubris, overweeing pride and thus gets into trouble.

The Nun's Priest's Tale is the only one of Chaucer's tales to reference an actual historical event. The tale is a fable ending in a moral lesson for the listeners, but it is technically a parody and quite humorous. Note, some believe the fable to be an allegory.