Incidents in the life of a slave girl is not a novel. As Jean Fagan Yellin shows in her biography, "Harriet Jacobs: A Life," everything Jacobs wrote about actuallly happened. This is important because (mostly) white male historians, as well as white male abolitionists did not believe that she could write such a book, and if she did, that it could all be true. For almost a hundred years, she was dismissed. Her editor and friend, Lydia Maria Child, repeatedly said that she herself did not write the book as charged. Ms Yellin did a gigantic service to women, to Harriet Jacobs, to women of color and to history by showing that this book is NOT a novel. It is, however a marvelous book that could change the world if people believed that a poor black slave could do what she did.
Thank you for your thoughtful comment. We might usefully describe the book as a fictionalized autobiography, given that Jacobs fictionalized the names of characters and that the book was generally accepted as a novel. Its continuing importance, as a testimony, exerts itself whether as novel or memoir. There is no doubt that Jacobs gifted the world with her life and work.