In the ante-bellum
South, communication between slaves often had to be hidden. Slave owners tried to limit communication
between slaves as much as possible in order to prevent planning of escape or rebellion
, and even in places where talking wasn't expressly forbidden there were still messages better kept secret.
Slave communities devised many ingenious methods for communicating, often methods that could be used in plain sight of their captors. Quilt codes were one method. Songs were a more widely available and generally useful method. In fact, many songs that might be familiar today as spirituals started out as code camoflage.
These songs are often described in broad categories, though few would fit into only one of these.
* Caanan = Canada Code within code, see?