When faced with an historic horror, most of us immediately think "How could they?" It is inconceivable that good people would stand by and do nothing in the face of genocide or chattel slavery. Some things seem so obviously wrong. But of course people are always doing horrible things while other people try to stop them, or stand by, frozen into inaction by all the other people who are also not doing anything, or don't even notice the wrongness so deeply embedded in their society.
Thus, the enslavement of millions of people. There's really nothing about it that isn't horrific: kidnapping, owning people, rape as a means of production. Kowal tackles this one head on, sending the Vincents out to deal with his family's sugar cane plantation in Antigua. She does an excellent job of looking at if from different angles to solve their problems. And although it's fantasy, there's no pretending like a little magic can fix all this.
Altogether a really interesting way to take Jane Austen and run with it. This particular series has the historical period down, and manages a gentle touch when addressing all the ugliness Austen eschewed. And a big plus, there is some humor and Jane does get some witty comments in, but it isn't just snappy comebacks.