If any of you have viewed or read my rants regarding Good Character, you may have heard me crack down on Character Background. Here, I will go more in detail of the purpose a background serves and when to use it.
What I find to be most deliberate about a backstory is to establish character. Whether it be to connect their twisted temper from past tragic experiences or, more differently, their burning enthusiasm from surpassing similar events. There's a defining bar of a past that metaphorically makes the character's spine, this allows the reader to interact with the character on a deeper level.
If you have ever played Dungeons and Dragons you may know the fun of having a character backstory. But, does the Dungeon Master or the players have to know about it? No. Bits and pieces of events makes things more natural in character development.
This can be done through dialogue or if written in first person, how a character reacts to certain things. Lets say your character was once in a car accident and the sound of thunder reminds her of it. So instead of writing long flashbacks to the incident, she gets uncomfortable maybe even scared to the sound. Just an example, but you see where I am going here? I can't emphasize SHOW don't TELL enough.
Sometimes, and I mean SOMETIMES, a background of a character can be shown in a preface. But, it depends on what is shown. If the whole story relies on details in the prologue, that may not be good, because some readers skip the preface. So rude! Seriously, you can't force the reader to read the preface and if its jam packed with details you're missing important elements to your storytelling later on.
Another way to show backstory could be to show how characters respond to your protagonist or antagonist or anyone. Say there was a fight between two characters your reader doesn't know about. When these two characters unite, whether it be casual or epic, you can show tension rather than explain or put the character in a thought process referring to why they dislike each other. Might seem cool in anime, but a book, no. A lot can be explained with natural dialogue and how other characters see each other.
Maria shook her head in disapproval, "You have some nerve."
She glared as Samuel stepped into her room through the window.
He held up his hands, a sad gleam in his eye, "Please, I only want to talk,"
"Talk to your new girlfriend."
Here we can get a few things. Maria doesn't seem to like Sam. Sam still seems to like Maria. They must have fought or she must have locked him out since he had to sneak in through the window. I know it doesn't imply how long ago these things took place, I probably could in a few more pages!
Off the top of my head I would suggest reading. Really study how the old masters did it. My brother strongly advised me to read the preface to 'Name of the Wind' by Patrick Rothfuss. If you really deny that preface isn't a place for character background, I highly recommend you read just the one page in that book. Its engaging and also, although you may not notice it at first, it shows a smidgen of character background. Subtle sweet and everything neat.
One last thing - as I explained in my '4 Do's and Don'ts of Character' video, think of your character as a person. I don't approach people saying, 'Hey I had bad days! Let me tell you all the bad days I had so you can understand why I am so crabby!' Your character is your person, don't try to explain everything about them in one swing.
Character Background is great for character and I believe a MUST. Learn to break up the correct pieces and place them throughout the story to where a reader can understand it.