There are a few things I want to point out.

First, all of the "witch" museums in Salem are commercial attractions. While they do present varied evidence, and not all of that evidence is necessarily wrong or out of date, there is very little pursuit in changing their narratives based on recent scholarship. There have been a few walking tours that are putting out accurate information, but even then it is hit or miss on who is running the tour that day. As a rule, tour guides rarely let the truth get in the way of a good story.

The Peabody Essex Museum acquired many of the actual items and manuscripts from the trials when they absorbed the Essex Institute. Unfortunately, the PEM has been attempting to re-brand themselves as a "mini-MFA" and refuses to have anything to do with the Hysteria. (If you still have the Haunted Happenings map from you visit, you'll notice the PEM is not located on the map across from the Visitor Center - this is because they didn't pay to advertise in the Halloween guide).

All that out of the way then.

No singular cause has been attributed to the Witchcraft Hysteria of 1692, and that is one of the reasons why it has remained so popular.

This wasn't the first case of witchcraft in the colonies, at least 22 people were executed on charges of witchcraft in a 50 year period prior to 1692. And in Europe, especially in the Germanic regions, charges of witchcraft ran rampant - estimates are usually around 50,000 executed across the continent as a whole. Many of the areas which saw the largest amount of persecutions were in areas of religious strife - where Protestant and Catholic religions intermingled - and in many cases religion can be seen as a major factor.

Then, consider that the War of Three Kingdoms (which culminates with the English Civil War) left Massachusetts in a precarious state. The whole of New England had been placed directly under royal rule, being stripped of their right to select their own governors. During the Witch Hysteria the new charter had just arrived in Boston - and with it a need to realign Massachusetts laws with the British law system. This lack of stability both at home and abroad was cause for concern in every congregation.

Another point worth mentioning is that King Phillip's War had ended not too soon before, and King William's War was ongoing in the west of Massachusetts and farther north up into Maine. This fighting was horribly violent, and oftentimes entire households or villages would be slaughtered by both sides. This violence flooded Salem and the surrounding areas with refugees fleeing war.

Also consider what was to be lost or gained by these accusations. The first cases were the daughter and niece of Samuel Parris, whose congregations had been attempting to force him out. From there it cascaded until over a hundred were accused (the total could be well upwards, many of these documents no longer exist). Those accused never fit a solid pattern though, and that is one of the reasons a singular cause can't be identified.

It's worth noting that there were often benefits to be had from people being accused to executed.

Of note, John Hathorne reportedly acquired a good portion of land from some who were executed, and George Corwin, the High Sheriff, is known to have acquired property from Phillip English after the latter fled with his wife. English spent the rest of his life attempting to recoup his losses from Corwin, who had never turned the confiscated property over to the courts as was required.

As for spectral evidence, both the Reverend Cotton Mather and Governor Phips stated it should not be accepted by the court but that accusations of witchcraft should be persecuted. Instead, both occurred. The acceptance of it by the court was unusual at best, and using it as the sole evidence was highly suspect. Some, Emerson Baker being one of them, make the argument that spectral evidence may have been connected to sexual abuse and actually been evidence of it. But there is no definitive way to know.

Ultimately what we do know is that 20 innocent people were executed, with others dying during imprisonment. All of those accused or executed were cleared of wrongdoing by the government in the years that followed, and many of those involved offered public apologies.