The Harry Potter films are certainly great entertainment, but they leave out a lot of important details from the source novels. Perhaps the worst offender of this is Half Blood Prince. This book is many a readers' favorite - it's not only exciting, but also very rich and expansive in scope.
It also offers a lot of intriguing details regarding the background and development of Lord Voldemort - development that the film adaptation woefully excludes. It's a shame, because there's a lot of great stuff to be read regarding Voldemort's humanity and development.
House Of Gaunt
Tom Riddle and his mother Merope were the last known descendants of the House of Gaunt. This family was one of the Sacred Twenty Eight, 28 families that remained pure blood into the 1930s. They were known for their ability to speak Parseltongue and for their pure-blood 'supremacy'. In fact, they were so devoted to keeping the family legacy pure that they would often resort to inbreeding and cousin marrying. The generations of inbreeding resulted in children with unstable and violent personalities - including Tom Riddle himself.
His Mother Cursed His Father
Voldemort's mother was pureblood Merope Gaunt, a descendant of the inbreeding Gaunt family. However, she went against her family's wishes and fell in love with a Muggle named Tom Riddle. However, Tom did not love her back. She in turn "forced" his love by bewitching him with a love potion. Once she became pregnant, she stopped her bewitchment in the hopes that Tom would love her naturally - or at least stay with her to help raise his baby. However, the plan did not work, and Tom left both Merope and his unborn son behind. This in turn led to...
Tom Was Born In An Orphanage
The Half Blood Prince does depict young Tom Riddle living in an orphanage, but it doesn't go into much detail. Merope was left utterly despondent following Tom's leave, falling into a very deep depression and being forced to live as a destitute pauper in the streets of London. It's also possible that her ability to produce magic was sapped from her as a result of her depression. On New Year's Eve 1926, Merope made her way to Wool's Orphanage and gave birth to Tom Riddle Jr. She then died within the hour, and Tom was subsequently raised in Wool's.
Tom Murdered His Father And Grandparents
Tom Riddle was left empty and hollow owing to both his heritage of inbreeding and lack of loving parents. When he was 16 years old he ventured to Little Hangleton and began investigating his parents' lives.
He met his uncle Morfin Gaunt, and through him learned about Tom Sr.'s abandonment. He tracked his father down and murdered both him and his parents (Tom's grandparents) in retaliation for his leaving his mother. He also framed Morfin Gaunt for the crime and escaped unpunished. The town didn't even mourn Tom Sr., as he was intensely disliked by the populace.
Violent Life In The Orphanage
The movie fails to go into detail regarding Tom's problematic and violent life in Wool's Orphanage. While he didn't know that he was magic, Tom could often "do things" with his mind and speak Parseltongue. After getting into a fight with Billy Stubbs, Tom used his magic to kill and hang his pet rabbit from the ceiling. He also took two other orphans, Dennis Bishop and Amy Benson, into a cave and did something so unspeakably terrifying that it horrified them into silence. What he did remains a mystery.
He Feared Death Above All Else
Voldemort isn't evil, and he didn't create numerous Horcruxes, for the mere sake of being evil and powerful. He actually had an incredible fear of death and did anything within his capabilities to protect himself from it. He didn't believe that his mother was magical, because if she was, she could have "protected" herself from dying. This intense fear of death is what caused Tom to produce such a curiosity in the dark magic of Horcruxes - if he could keep parts of his soul entombed in various objects, he could never die.
Dumbledore Was The Only One To See Through His Facade
While attending Hogwarts, Tom Riddle became a model student. He was outwardly friendly, very smart, a suck up to his teachers, and by all accounts, a perfect student.
However, this was merely a facade, as he knew to keep his true intentions hidden from the world. The only one to see through the facade was Dumbledore, who knew of his problematic past in the orphanage and the darkness that young Tom exhibited upon their first meeting. This in turn caused Tom to hate Dumbledore, and he kept his distance throughout his time at Hogwarts.
The First Death Eaters
While attending Hogwarts, young Tom Riddle amassed his first Death Eaters. Tom amassed a "gang," so to speak, which consisted of fellow Slytherins who doted on Tom's every word. These students included bullies looking to Tom to enact more cruelty, ambitious students who saw the intelligent Tom as a kindred spirit, and weak-willed students seeking friendship and protection. Of course, Tom didn't actually care for his "friends" and often utilized them for his own nefarious purposes. They were puppets and nothing more.
His First Two Horcruxes
Upon learning of Horcruxes, Tom immediately got to work in his creation of them. The first Horcrux he created was from his diary, purchased at a Muggle book store in London. After opening the Chamber of Secrets and indirectly murdering Myrtle (who would go on to become Moaning Myrtle), he used the magic to infuse his diary and turn it into a Horcrux. After learning about multiple Horcruxes from Slughorn, he used the murder of his father to turn Gaunt's ring, which he had taken from his uncle Morfin, into his second Horcrux.
The Origins Of Lord Voldemort
In Chamber of Secrets, young Tom Riddle reveals that Lord Voldemort is an anagram of his birth name, Tom Marvolo Riddle. Tom had grown despondent after learning that his father was a Muggle - both because of his pureblood supremacy and because Muggles were prone to death. As such, he wished to distance himself from his Riddle heritage. He turned his birth name into an anagram, officially creating the title of Lord Voldemort.