I struggled to get through this book and stopped reading after about sixty percent. I don't rate books I did't finish and frequently don't write a review, because I feel it unfair to review a partial book. However, in looking through the other reviews there were enough folks who agreed with my assessment, that I felt confident in saying why I put this book down, without being unfair. The character Sisi, didn't grab me in any way. I had some initial sympathy for her as I learned her backstory (from an earlier book) and felt I'd like to read that one--there seemed to be conflict and character development in it reminiscent of Catherine the Great's initial years in Russia. 
 Unlike Catherine who grabbed the chance to rule with intelligence and insight, Sisi runs away from husband, family, and obligations to ride and recover from her onerous duties. I understand her motivations and I like horses and riding, but page after page of lamentations and horses doesn't make for compelling story-telling--at least not the kind of stories I like to read. Given all the 4 and 5 star ratings, I'm in the minority, but c'est la vie. I do give kudos to the author for her extensive research and lush writing. 
 NOTE: I received an ARC through an early reading program in exchange for an honest review. I hope the publisher doesn't regret it.