Salem Witch Trials History
The Crucible is based on the Salem Witch Trials in Massachusetts in 1692. It started off with a couple of young girls saying they were possessed by the devil and with special abilities including being capable to tell who had been committing witchery and satanic actions/thoughts. This histeria expanded into something very out of control, with accusations going through the roof. So much, in fact, that even two dogs were accused of witchcraft. This paranoia took over Salem with neighbors accusing neighbors. They were heavily puritan, and would pray rigorously. There religion didn’t allow any form of dancing, theatre, and so on. Because they believed so deeply in Jesus Christ, it was not completely far fetched to give fault to the unexplainable with miracle/satanic work. There has been much speculation to what exactly was the cause of this hysteria.
("Salem Witch Trials")
Ergotism Theory
There was one theory that Ergot, a type of fungus, spread through the rye and other wheats which were consumed by the public. This fungus had effects including hallucinations which most definitely have a connection to the girls who said they saw animals and creatures.
(Spanos, Nicholas P., and Jack Gottlieb, “Ergotism and the Salem Village Witch Trials”)
Weather Theory
This theory is basically on the idea of scapegoating. They were in difficult financial times as well as difficult conditions. During the winter, Emily Oster discovered, there was a rise in accusations so it is very possible that as times got colder -more difficult and obstacles became bigger and more difficult to evade- they were blamed on witchery. Thus, if one’s crops weren't growing well or if their cow fell sick, they would maybe blame it on their neighbor or enemy.
(Franklin G. Mixon Jr.. “Weather and the Salem Witch Trials”)