Cracker
Cracker, sometimes white cracker or "cracka", is a colloquial term for white people, used especially for poor rural whites in the Southern United States. It is also at times used indiscriminately and pejoratively against any person of white background. However, it is sometimes used in a neutral or positive context or self-descriptively with pride in reference to a native of Florida or Georgia

"Cracker" has also been used as a proud or jocular self-description. With the huge influx of new residents from the North, "cracker" is used informally by some white residents of Florida and Georgia ("Florida cracker" or "Georgia cracker") to indicate that their family has lived there for many generations. However, the term "white cracker" is seldom used self-referentially and remains a "slur" for Caucasians.

It has been suggested that white slave foremen in the antebellum South were called "crackers" owing to their practice of "cracking the whip" to drive and punish slaves. Whips were also cracked over pack animals, so "cracker" may have referred to whip cracking more general
"I should explain to your Lordship what is meant by crackers; a name they have got from being great boasters; they are a lawless set of rascalls on the frontiers of Virginia, Maryland, the Carolinas and Georgia, who often change their places of abode." 1766, G. Cochran