Sometimes you just have to skim read and that's what I did with this book. I started out with good intent to read it all fully, but my interest was in Sally Hemmings, Thomas Jefferson's slave "wife". The author's interest was in the entire family that Sally was from and that was interesting up to a point. There were innumerable tangents that I just had to skip over when I realized that the length of the book was entirely due to all the divergence and historical contexts. Don't get me wrong, I think the author did an amazing job of research considering the little information that is available on this family. She was a masterful detective in fact surmising from the lack of information what must have been the situation and circumstances affecting Sally and other Hemmingses.
If you are a student of history and particularly interested in the people that played a part in Thomas Jefferson's life, I recommend this book to you.