From the author's 2012 Q & A at the Guardian:
How did you come to write River of Smoke?--Marshal Zeringue
River of Smoke is the second novel in a series that began as a trilogy (I call it the Ibis Trilogy). The first book was Sea of Poppies; soon after I started writing it I realised that the characters and their stories would take more than one book. The books are not meant to be a single linear narrative (if that had been the case then it would have been a single, very long book). I always thought of the relationship between the books as a tangential one (as, for example, in Lawrence Durrell's Alexandria Quartet). Some of the characters recur, but each book has its own themes, settings, mood, spirit and so on. In this sense each of the books can be read as a complete and self-sufficient novel in its own right.
What was most difficult about it?
The setting. Most of the action takes place in Canton (Guangzhou) in 1838 and 1839. To get the background right was a real challenge: I had to...[read on]