Didn't the British exile lots of prisoners to North America in the early settlements? Maybe there's also a genetic connection? ;) Just joking. I think overal

Didn't the British exile lots of prisoners to North America in the early settlements? Maybe there's also a genetic connection? ;) Just joking. I think overall happiness of people is also really important. The more unhappy people are the more violent they get. People in Skandinavia are generally quite happy folks: Easy access to education, internet, food, health care, low poverty etc...