How does Sophie’s English nationality and the setting of the novel in England influence the story?

If Sophie was not English, then the setting of the story would be completely different. It’s outcome would also potentially be different. For example, if Sophie lived in the United States instead of England, she couldn’t just ask the Queen of England for help. She would have to turn to the President of the United States for help instead. The many customs mentioned in the book would also be different. For example, many places around the world do not have tea like the English do.