Lord Voldemort - Wikipedia

In a 1999 interview, Rowling claimed Voldemort was invented as a nemesis for Harry Potter, and she intentionally did not flesh out Voldemort's backstory at first. "The basic idea [was that Harry] didn't know he was a wizard ... And so then I kind of worked backwards from that position to find out how that could be, that he wouldn't know what he was. ... When he was one year old, the most evil wizard for hundreds and hundreds of years attempted to kill him. He killed Harry's parents, and then he tried to kill Harry—he tried to curse him. ... Harry has to find out, before we find out. And—so—but for some mysterious reason the curse didn't work on Harry. So he's left with this lightning bolt-shaped scar on his forehead and the curse rebounded upon the evil wizard, who has been in hiding ever since."[8]

In the second book, Rowling establishes that Voldemort hates non-pure-blood wizards, despite being a half-blood himself. In a 2000 interview with the BBC, Rowling described Voldemort as a self-hating bully: "Well I think it is often the case that the biggest bullies take what they know to be their own defects, as they see it, and they put them right on someone else and then they try and destroy the other and that's what Voldemort does."[9] In the same year, Rowling became more precise about Voldemort. She began to link him to real-life tyrants, describing him as "a raging psychopath, devoid of the normal human responses to other people's suffering".[10] In 2004, though, Rowling said that she did not base Voldemort on any real person.[11] In 2006, Rowling told an interviewer that Voldemort at his core has a human fear: the fear of death. She said: "Voldemort's fear is death, ignominious death. I mean, he regards death itself as ignominious. He thinks that it's a shameful human weakness, as you know. His worst fear is death."[12]

Throughout the series, Rowling establishes that Voldemort is so feared in the wizarding world that it is considered dangerous even to speak his name. Most characters in the novels refer to him as "You-Know-Who" or "He-Who-Must-Not-Be-Named" rather than say his name aloud. In Harry Potter and the Deathly Hallows, a "taboo" spell is placed upon the name, such that Voldemort or his followers may trace anyone who utters it. By this means, his followers eventually find and capture Harry and his friends Ron Weasley and Hermione Granger. In the second book, Rowling reveals that I am Lord Voldemort is an anagram of the character's birth name, Tom Marvolo Riddle (in translated editions of the book, his middle name or entire birth name is/are often changed in order to allow anagrams to be formed in other languages).[13][14]

According to the author, Voldemort's name is an invented word.[15] The name Voldemort is derived from the French vol de mort which means "flight of death" or "theft of death".[16]