The personal use or threat of violence is the most effective means to discourage those who would misuse or deprive an individual. It is practiced not only in traditional societies but by those outside the law, like gangs and some inner city communities.
In most societies for thousands of years an individual's security largely depended on the ability to maintain a credible threat of violence. His interests were likely to be violated by competitors unless the competitors were deterred by fear of retaliation. With the development of the state, its monopoly on the legitimate use of force grew as well. In the Eleventh Century, William the Conqueror outlawed private vengeance in England and made homicide a crime against the state instead of a private wrong.