I love backstory. Characters with rich histories that form their personalities and worldviews are what drive much of the world’s greatest literature. Backstory is what gives a character’s beliefs and actions psychological validity, and creates an access point for readers to understand and even predict the motion of the story.
Of course, there is a right and wrong way to go about including backstory in your writing. In life, everything we do is directly linked to something in our past, extending the chain back to our birth, or even before; our personality is affected by who our parents are, who in turn were affected by their parents, who in turn… Follow this to its logical conclusion and every story ever written would begin in the Garden of Eden.
Mary Shelley’s Frankenstein (which I am currently reading) is a good example of why this is a bad idea. Not content with showing us how Victor Frankenstein’s fascination with “natural philosophy” arose, she chose to take us not only into his early childhood, but all the way back to how his parents happened to meet. The story doesn’t even begin until Chapter Five! By that time, only the fixed idea that the book is a classic, and must therefore have some merit, kept me reading. Fifteen chapters later, I can genuinely say I am enjoying the story, although I’m thoroughly disgusted by stupid Victor. But I’ll save that for my Goodreads review.
So, how much backstory should we include? Ah, time to bring up the good old “Iceberg Principle.”
Just as the main bulk of an iceberg is hidden underwater, the main bulk of backstory should remain hidden. The history is there, manufactured by the writer and affecting the character’s attitudes and actions, but the reader is only shown what is absolutely vital for understanding, and left to infer the rest. The general rule of thumb is to show ten percent of a character’s history.
Readers aren’t dumb. A trace of memory, a short conversation between two characters, is enough to reveal volumes.