What events in history have solidified or destroyed communities?

When thinking of events that destroyed or solidified a community I think of the Salem Witch Trials. Salem Witch Trials were "court hearings" that were held in a community when someone was accused of performing witchcraft. Some people were accused of being a witch but really weren’t and their lives were taken because of the things they would do to try and prove they were a witch. The most common thing they did was hang the accused. If they weren’t dead when the people of the community and the court officials came back, that person was a witch. As you can see that if the person died they weren’t a witch, but then that means the officials killed an innocent person. This destroyed the community because anyone who had some sort of problem with someone else they would accuse the other to get them back. If there was any hate or disagreement, one person would accuse the other. Also, when someone accuses someone, not everyone will agree with the person accusing someone so they will develop a hate toward them and it will happen again and again. It happens in the same pattern.