This is not a romance; it is historical fiction. Trade Wind is about Zanzibar, an island off the coast of Africa. Kaye traces the slave trade, political uprisings and a cholera epidemic in the 1850s and 1860s. The story centers around Hero Hollis, a girl who steadfastly (and arrogantly) believes she can change the people and the country of Zanzibar. She's contrasted with Rory Frost, an arrogant (and kind of immoral) slave trader. It's a study of right and wrong and how life is actually not always as it appears.
I really enjoyed the story. It's sprawling, but gives a really good taste of what life was like in Africa. Kaye did her research and it shows.
My only complaint was a lack of insight into some of the character's emotions. Other than that, I recommend this book.