I read Astraea, the first book in the trilogy of which this is the second part, and found it interesting though not compelling. Here the story moves forward 25 years and the child of Elizabeth of Bohemia and an ex-African prince, ex-slave is now an adult of mixed race and living in Holland. The other reviewer here has commented extremely favousrably on the historical background, and while I'm not as qualified to tell, I would expect that to be the case given that Stevenson is an English professor.
But however good the 'history' the book just doesn't have a compelling enough plot or characters to make it come to life. Balthasar and Aphra Behn are just cardboard, which is a huge disappointment. This might be an accurate depiction of Restoration Europe but it's a dull novel, in my opinion, with no life to it. I struggled with it then finally abandoned it on the tube hoping that perhaps someone else will get the enjoyment from it that completely escaped me. A huge disappointment I'm afraid.