Tom Marvolo Riddle (31 December, 1926 – 2 May, 1998), later known as Lord Voldemort or alternatively as You-Know-Who, He-Who-Must-Not-Be-
Named, or the Dark Lord, was a half-blood wizard considered to have been the most powerful and dangerous dark wizard of all time. The only child and son of a wealthy Muggle man Tom and Merope Riddle via the coercive use of a love potion, Riddle was raised in the Muggle-run Wool's Orphanage after his father abandoned his new family on the streets of London when the potion's influence was lifted, and his mother died moments after giving birth to and naming him after his father and maternal grandfather, Marvolo Gaunt.
Riddle began attending Hogwarts School of Witchcraft and Wizardry in 1938 and was sorted into Slytherin house. Some of his early activities included the opening of Salazar Slytherin's Chamber of Secrets and the use of its monster to attack Muggle-born students; several months' service as a purchasing agent for the Dark artefacts shop Borgin and Burkes; the ability to speak Parseltongue; and the attainment of immortality between the years of 1942 and 1998, a process begun upon the creation of his first Horcrux at the age of 16.
Splitting his own spirit into a total of eight fragments, Riddle created seven Horcruxes; one unintentionally and without his knowledge — Harry Potter. Abandoning his 'Muggle' name, he became the self-proclaimed Lord Voldemort, which was an anagram of his birth name. He commanded a veritable army of wizards and Dark creatures, committed numerous murders personally and through his followers, and on one occasion nearly succeeded and on a later occasion did succeed in taking over the Ministry of Magic by installing a puppet Minister.
Voldemort was ripped from his body in 1981 after attempting to kill Harry and, though unable to die, was not able to regain a permanent and physical body until 1995, thus spending the intervening fourteen years "a shell, less than the meanest ghost", but alive. He was finally killed by his own backfiring curse after Albus Dumbledore and Harry Potter, following Dumbledore's death, succeeded in destroying all of his Horcruxes.
Unknown to most however, Voldemort's legacy and bloodline would live on through his daughter Delphini ("Delphi"), whom he conceived with his loyal follower Bellatrix Lestrange; sometime after the Battle of the Department of Mysteries in 1996 and before Voldemort's death at the hands of Harry in 1998.
Riddle's broken and mutilated soul was then trapped in Limbo for eternity, unable to move on to the afterlife or even return as a disembodied spirit.
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