The Blockade Runners is set during the American Civil War. It's a fun little novella by Jules Verne that deals with a blockade runner heading to Charleston, South Carolina.
The captain, a member of an English merchant family, take on a sailor (a very unusual character - get this to watch him) at the last minute. He also has to take on the sailor's nephew. This changes his life in a manner he can't possibly imagine.
It's a free book for the Kindle, so give it a shot. It's a fun, quick read. First time I read a bit of Civil War fiction like this.
Here's a hint - Romance on the High Seas!