Bitter Greens is a lot of things: historical fiction, historical fantasy, fairy tale retelling. Most importantly, though, it's great fun, containing grand stories worthy of fairy tales, with the complexity and historical background of a good adult novel.
Slightly over half the book is narrated by Charlotte-Rose de la Force, a lady-in-waiting in the court of Louis XIV of France. (She was an actual historical writer, one of the first to tell the Rapunzel fairy tale.) We first meet her at age 47, when she's banished to a convent for offending the king; her chapters alternate between her struggle to adapt to her new life and her dramatic backstory. While these chapters have a fairy-tale style, Charlotte-Rose's story is strongly grounded in the turbulent historical era and contains little to no magic.
The rest of the novel is a retelling of "Rapunzel." The majority of these chapters focus on Margherita, the young Rapunzel character, but there's also a chunk belonging to Selena, the witch, in which we get her tragic backstory. These sections contain strong fantasy elements, but still have a historical framework: Italy, particularly Venice, in the 16th century.
The plot jumps around in time, looping backward and forward through the characters' lives; this works well, as connections and similarities between the three main characters build throughout the book. The plot is highly entertaining, Charlotte-Rose's story as much so as the Rapunzel tale. (I can see why Forsyth decided to devote so much time to the writer, as hers was clearly a story begging to be told. The more unlikely elements, such as the dancing-bear scheme, apparently come straight from the historical record.) For me at least, the balance of fairy tale and realism is just right: the story has the larger-than-life quality of a fairy tale, without becoming too simple or dreamy. In isolation, Charlotte-Rose's story might seem a little too easy or cliché, but interwoven with the Rapunzel tale it works splendidly.
The protagonists are the sort of heroines one would expect in a modern fairy tale: brave and good and resourceful. Charlotte-Rose and Margherita seem created with an eye more to making them likeable than realistic; but they are indeed likeable, with sufficient depth to sustain their ultimately satisfying stories. The characterization might at first appear black-and-white, but soon proves somewhat more complex. And while Margherita fills the traditional Rapunzel role, she's a capable girl who provides an answer to many of the problems modern readers have with the character (for instance, why she doesn't just climb down on her own hair).
Selena's story, though, is rather less satisfying. She reads like a darker echo of Charlotte-Rose, and while the author probably didn't intend this interpretation, I find her chapters most interesting when viewed as "the witch's backstory as imagined by Charlotte-Rose." Her character doesn't quite come together the way the other two do, and the inevitable tragedies in her life--having nothing to do with old age--don't explain her obsession with eternal youth. But, in fairness, I may be overly critical on this point--since reading Wicked I've found all other attempts to create wicked witches totally lame.
Bitter Greens has a good sense of place, and does a great job of maintaining that perfect fairy-tale mood. It's not great literature, but the writing style is adequate. Do note that this is definitely a book for adults, with some rather explicit scenes. These become rather repetitive: there are at least 5 relationships in the book, and while they go in different directions, most of the sexual encounters feel nearly interchangeable.
Finally, the historical element is quite interesting; the author clearly did her research, and the French sections in particular are full of lively detail without bogging the story down.
In the end, I enjoyed this book and would recommend it to anyone who enjoys historical fantasy or fairy tale retellings. What I don't understand at all is why it's been published nearly a year in Australia and has yet to come out in the U.S. This seems like a book that would have a large and appreciative audience--better get on that, publishers!