I tend to get interested in back story to the extent that I lose track of the main plot. I do this both as a writer and as a reader, but it’s obviously more of a problem for me as a writer. Right now I’m stuck in a novel in which back stories have overwhelmed the simple plot I had going and are taking that plot off in four directions at once.
The aggressive back story problem is solvable to some extent in a series that has recurring minor characters. The bios those characters haul around with them can often provide the main plot of the next book. All the same, the magnetic pull of assorted back stories can slow things down. We are told that the reader needs a crisp, fast-paced narrative. I don’t, but then I read too fast.
When I’m writing a novel, I think hard before I introduce a named character, because naming them seems to make them people, “rounds them out.” Once my characters are named, they develop back stories almost by magic. In Aspects of the Novel (old book), E.M. Forster talked about round characters and flat characters. Round characters are like real people in that they always have the ability to surprise you by what they do and what they have done, whereas flat characters are utterly predictible. Sometimes flat characters like Mr. Micawber can be summed up in a single phrase. Dickens used flat characters very effectively, but, according to Forster, Jane Austen created nothing but round characters–always three-dimensional, always capable of surprising the reader. Miss Bates in Emma, for instance, is as close to a cartoon character as Austen gets, but just when Miss B. seems to be summed up by her own silliness, she has a moment of great dignity that makes Emma (who is downright spherical) look bad.
Most mystery writers who do series novels lean heavily on back story. Dorothy L. Sayers springs to mind. In contrast, most of Dick Francis’s books have been stand-alones, and the back story didn’t carry from one book to the next. Some series writers seem to have a template paragraph they pull up and insert to remind the reader of what went on in other books. I find that clumsy, both as a writer and as a reader, so I try to avoid referring to my earlier books and to make each story readable on its own. However, I’d welcome suggestions from anyone on how to handle the problem in other ways.
What should be done about bodacious back story? Chop it out or let it develop? A novel is a thought experiment, a virtual society. As Benedick says in another context, the world must be peopled, and my feeling is that each new book in a series should introduce more new people than recurring people–not to mention fresh conflicts and ideas. But the back story is always there.