CRIMSON ANGEL, by Barbara Hambly

13/series, starring Benjamin January, a free man of color trying to survive in 1838. First in New Orleans, where his wife Rose and their son Baby John live an edge-of-disaster life. Rose's brother visits from America, he's trying to find family treasure supposedly buried in ancient family holdings in Haiti. The former French colony, scene of inhuman treatment of slaves that had led to full-scale rebellion, looks upon visitors as threats to be summarily removed. Benjamin and Rose both decline to join the treasure hunt, but when her brother is murdered, Click below for more...
and a blatant daylight attempt is made on Rose, Benjamin understands that, like it or not, in order to save his family he must get to the bottom of the mystery. They flee under cover of night to Barataria Bay, at the mouth of the Mississippi, then catch a boat to Havana, where the first member of Rose's slave-owning family lives in splendid isolation. From there, it's a progression of increasingly perilous days until - deep in the treacherous hills of Haiti - the final, hideous "treasure" is found. Excellent tale in a series of excellent tales, this is a 5. While the scenes involving slavery are disquieting, they are chillingly real.
Find the author at www.barbarahambly.com