Imperius Curse

"Total control. I could make it jump out the window, drown itself, throw itself down one of your throats..."

- Barty Crouch, Jr. as Alastor Moody

The Imperius Curse is one of the three Unforgivable Curses. When cast successfully, it places the victim completely under the caster's control, though a person with exceptional strength of will is capable of resisting it. The curse's incantation is Imperio.

Effects
"It was the most wonderful feeling. Harry felt a floating sensation as every thought and worry in his head was wiped gently away, leaving nothing but a vague, untraceable happiness. He stood there feeling immensely relaxed, only dimly aware of everyone watching him."

- Harry Potter under the Imperius Curse

The victim of an Imperius Curse is placed in a calm, trance-like state in which all feeling of responsibility and anxiety is banished. They may then be directed to do anything the caster wishes, including crimes such as murder, political corruption, embezzlement, and so on. It is unknown if this hypnosis spell can affect physical capabilities, such as forcing a victim a task such as being stronger or casting spells far above their level, although Neville Longbottom was able to perform a series of "quite astonishing gymnastics" under the curse that he would not normally be capable of.

If the Imperius Curse is performed poorly, then the victim would have their mind addled, an example being Muggle Junior Minister Herbert Chorley. It seems the damage is long-lasting, as Chorley was sent to St Mungo's Hospital for Magical Maladies and Injuries to recuperate.

Resisting the Imperius Curse is possible, but requires great strength of will and character. Harry Potter, Barty Crouch Sr and Barty Crouch Jr each learned to resist the curse after being subjected to its effects. Resisting the Imperius Curse is similar to Occlumency, which requires a great amount of willpower.

According to Harry, using the Imperius Curse caused him to experience "a feeling of tingling warmth that seemed to flow from his mind, down the sinews and veins connecting him to the wand and the curse it had just cast". He believed that his curse might not be very strong, however, thus the sensation from casting a more powerful Imperius Curse may be more intense.

It is possible for someone who has been Imperiused to place others under the curse as well. For example, Madam Rosmerta, who had been Imperiused by Draco Malfoy sometime during the 1996-1997 school year, was able to place Katie Bell under the Imperius Curse in an attempt to deliver a cursed necklace to Albus Dumbledore. It is also possible that the Death Eater Yaxley used the Imperiused Pius Thicknesse to place other high-ranking members of the Ministry of Magic under the curse in order to facilitate the overthrow of Rufus Scrimgeour.



History of Use
Death Eaters made use of the curse in both the First and Second Wizarding Wars to force innocent people to do their bidding. For example, Lucius Malfoy used the Imperius Curse to force Broderick Bode and Sturgis Podmore to try to steal a prophecy from the Department of Mysteries in 1996, and Yaxley placed the Imperius Curse on Pius Thicknesse as part of the plan to take over the Ministry of Magic in 1997.

Ironically, many Death Eaters, such as Lucius Malfoy, avoided imprisonment in Azkaban after Voldemort's first defeat in 1981 by claiming that they had been under the Imperius Curse. As such, it became the Ministry's work to determine who is lying, even though many "victims" have managed to deceive them.

Harry Potter and Albus Dumbledore speculated that Merope Gaunt may have used the Imperius Curse on Tom Riddle Sr. to force him to marry her, although Dumbledore thought it more likely that she used a love potion.

Other Known Uses

 * Herbert Chorley, a Muggle Junior Minister, was the victim of a "poorly-performed Imperius Curse." The resulting symptoms included impersonation of a duck in public.

Etymology
This curse takes its name from the Latin imperiosus, meaning "commanding, mighty, and powerful".

Notes and references
Impero Imperius-Fluch