I planned to write a novel about two male soldiers, one Union, the other a Confederate. But in doing my research I kept running across extraordinary women, on both sides, who were involved in fighting the American Civil War. This includes Kate Warne and Hattie Lawton, who were Pinkerton detectives who conducted espionage for the Union. Other notables are Pauline Cushman, who spied for the Union spy and Rose Greenhow, a Confederate spy. As I began writing about the men, Rachael, who became the protagonist in my novel, began to take shape and rise out of the draft pages until she stood in front of me. After that, I simply told her story.