Unforgivable Curses are three types of Dark magic with severe penalties if they are used. They are outlawed by the Ministry of Magic.
History[]
In 1717, three types of curses were classified "Unforgivable" by the Ministry of Magic. They are the Killing Curse which causes instantaneous death, the Cruciatus Curse which inflicts excruciating pain, and the Imperius Curse which enables the caster to have total control over their victim.[1]
In his notes on The Tales of Beedle the Bard, Albus Dumbledore suggests that the character of Babbitty Rabbitty threatened to use the Cruciatus Curse on the King because it could produce the sensation she describes. The story was written in the 15th century when the curse was not yet prohibited. If so, this is the earliest known reference to an Unforgivable Curse.[1]