In the fictional world of the Harry Potter series, the Death Eaters constitute a group of wizards and witches, led by the dark wizard Lord Voldemort, the chief antagonist of the series, who seek to purify the Wizarding community by eliminating the Muggle-borns. They also try to create a new order through the Ministry of Magic and cause fear among the Wizarding community by terrorising and killing important officials and other enemies of the Death Eaters, chiefly the members of the Order of the Phoenix.
According to author J. K. Rowling, the original working title for the Death Eaters was "The Knights of Walpurgis".
Death Eaters recognise one another by the Dark Mark on their left forearm, a sign created by Voldemort to summon them instantly to him. Their typical attire includes black hooded robes and masks. The Death Eaters, as a group, first appreared in the novel Harry Potter and the Goblet of Fire, although individual members of the group had appeared in earlier books in the series, such as Lucius Malfoy, who first appeared in Harry Potter and the Chamber of Secrets.
The Death Eaters first existed some twenty years before the events of the books, torturing and murdering anyone who was a Muggle, opposed them, or was believed to have information which could aid in or harm their rise to power. Around ten years after the Death Eaters first surfaced, a Seer named Sybill Trelawney made a prophecy about one who would have the power to defeat Voldemort forever. The prophecy could have referred to two different boys, Harry Potter or Neville Longbottom; however, for reasons unknown, Voldemort chose to go after Harry. Acting on information from James and Lily Potter's Secret-Keeper , Voldemort attempted to complete the prophecy and kill his infant rival. Due to Harry's mother's sacrifice to save her son, Voldemort's deadly curse rebounded off Harry and disembodied Voldemort.
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