Salem Witch Trials (1692, Christians vs. the imperfectly orthodox)

Apparently started as something of a prank by some pre-adolescent girls, this quickly grew into hysteria. A few dozen people hung, more disgraced, and (funny how this always happens) most of their land and cash wound up with the oppressors.

I think it's pretty sad that people were killed, on the word of a pre-teen girl.

A siezure of hysteria in what was an isolated, fear-ridden and ignorant place. In a rather embarrassing personal note, I'm directly descended from one of the prosecutors.