When we read the original works in English, we often refer to the knowledge about the cultural background, because the lack of it leads to the unintelligibility.
I think you can read the preface at the beginning of the book or the
outline of the back cover or something like that to get an idea of the
whole book, or look it up on the Internet, which might be helpful.
If the lack of background knowledge has influence your understanding, I
think it's a necessary for you to search for it.Another suggestion is,
you can skim the summary of the book and search culture knowledge as preparation.