You guys are cracking me up! Never been to New Orleans, but absolutely intend to some day. Jim, you brought up an excellent point with migrants bringing these types of dirks over from their home countries. This is the 'melting pot', after all. I have seen several examples of gambler dirks and boot knives with thin, stiletto blades. One, I believe, was identified as belonging to a Confederate soldier.
All this makes me want to watch "Silverado" again. Remember? Jeff Goldbrum playing the villain with the boot dagger?