The Puritan society and belief system is to blame for the Salem Witch Trials. With out their vindictive beliefs on witches, no one would be tried and killed for their strange practices. They would just be a weird abnormality of the community. The Puritans believes that they should be killed, and that's why the Salem Witch Trials were so bloody.
Because of the Puritan belief that witches existed and were products of Satan, the Salem Witch Trials were a result of mass hysteria resulting from the belief that people were being possessed by those witches. Because any religious belief carries with it a certain amount of closed-mindedness, Puritan societies believed that witches were definitely the cause of certain happenings, instead of trying to find the real reason for them.