“Noiro of the starlit sky,
By grace he gave his life to die,
He alone did fury brave,
The lives of innocents to save.”
When done right, background doesn’t slow down the plot, it adds to it and increases tension, mystery or resolution. Noiro is an ancient warrior from the annals of Pangea. Who he is, what he accomplishes and how he dies shape the main characters development, and the decisions he must make.
A simple stanza sung by the main character at an appropriate time provides the reader with an insight they might not otherwise have gained, while simultaneously adding to the rich tapestry of Pangea’s mythology. I could have used pages to explain his back story, and initially I did. Then I realised it wasn’t necessary. A couple of revelations dotted throughout the book do the job just fine.
You need background, but add it wisely, and use it well.