The September issue of Scientific American magazine has an article I highly recommend you read: The Secrets of Storytelling: Why We Love a Good Yarn (by Jeremy Hsu).
It discusses how storytelling is a universal and timeless part of every culture, and what storytelling reveals about how our minds evolved and function.
Some interesting quotes:
Storytelling is one of the few human traits that are truly universal across culture and through all of known history. [...] People in societies of all types weave narratives, from oral storytellers in hunter-gatherer tribes to the millions of writers churning out books, television shows and movies.
Whether fiction or nonfiction, a narrative engages its audience through psychological realism--recognizable emotions and believable interactions among characters.
As our ancestors evolved to live in groups, the hypothesis goes, they had to make sense of increasingly complex social relationships. Living in a community requires keeping tabs on who the group members are and what they are doing. What better way to spread such information than through storytelling?
There's an interesting discussion of how common romance story themes reveal basic human needs and wants!