Backstory is a collection of details readers need to know about a character or a plotline in order to make sense of what’s happening. But backstory is also embedded behind the current timeline…it is part of a character’s history before the book opens or is a collection of events that occured that get the plot rolling. If you start by filling in readers with all this information, the opening section (roughly the first 80 to 100 pages) won’t capture interest.
When you’re writing the first draft, it’s fine to write all the backstory first. This is the way most people write because it puts things into a chronological order. It can make the writing process much easier. So don’t shy away from writing things in the order they happen.
The rewriting process for the second (and possibly other drafts) corrects this issue. Take all that backstory and pull it into a different file. Then find places in the plotline where chunks of this information can be dropped in. By interweaving the backstory with the current timeline, your novel will become more compelling. You’ll also find that the backstory takes on a deeper meaning when it is placed right beside the point at which readers need to know some historic fact.