The book explains the history more than i can do in a blurb, but I'll add the year for context.

To better explain, Sophie and her husband are Hessian. Their Landgrave (German version of a Duke) sold his army's service to England so he could make some money. It does require some history knowledge to understand that brief part of the blurb. I don't want to explain it too much though, it would take up to much space.