Does the South have a culture of violence? Many writers haved claimed that the South is more likely than other regions to turn to violence to deal with perceived problems, but I haven't seen much systematic data to back it up, expect for higher rates of violence.
The General Social Survey asked 7,697 men if they would approve of someone hitting a stranger who was drunk and bumped into the man and his wife. Here are the percent who answered yes by region of the country:
Percent of men who are pro-violence
New England 5.2
Middle Atlantic 6.6
East North Central 7.2
West North Central 7.3
South Atlantic 11.2
East South Central 14.7
West South Central 11.4
Clearly, most men don't think a quick resort to violence is right, but there are a few especially in the South. Now, who knows the causal connection between attitudes, behaviors, and other related variables, but we can say that the South, especially the East South Central division (TN, KY, MS, AL) has more violent, pro-violent, and low IQ people than other regions.
Let's see how well violent attitudes match patterns of actual violence:
Percent who are pro-violent
Puerto Rican 9.3
American Indian 10.4
Ages 61+ in 1972 18.1
Ages 18-30 in 1994 4.0
Overall, these estimates are not consistent with patterns of violent behavior. Chinese and Japanese Americans, for example, are on the high end with respect to values, but are on the low end of actually assaulting someone. Perhaps we're not validly measuring attitudes, but there is little reason here to think that behavior matches values.
I included the last two estimates to show that pro-violent attitudes are more common among older people surveyed in earlier years. The GSS hasn't asked the question in this decade, but the 70s through the first half of the 90s show decreasing support for violence.