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We first see Neville when he's being told off by his Gran, round-faced and teary as he looks for his toad Trevor. Hermione Granger decides to help him look for it on the Hogwarts Express, leading to her first meeting with Harry Potter and Ron Weasley. He takes a long time to be Sorted, eventually ending up in Gryffindor. He embarrasses himself in front of all the school by running to his table with the Sorting Hat still on his head.
He soon proves to be forgetful as he gets caught in a trick staircase and makes mistakes in his lessons, most notably in Potions by melting Seamus Finnigan's cauldron, earning the scathing treatment of Professor Snape. Neville is terrified of his first flying lesson and injures himself quickly. He forgets password to the Gryffindor Common and ends up getting caught in Harry and Ron's attempt at a midnight duel along with Hermione. The experience terrified Neville.
He also attracts the attention of Slytherin bully, Draco Malfoy, who keeps jinxing him and telling him that he isn't brave enough to be in Gyffindor. In Harry's second ever game of Quidditch, when Malfoy goads Ron to the point where Ron physically attacks him, Neville joins in to help. He takes on both of Malfoy's larger friends, Crabbe and Goyle, ending up knocked out.
Despite Neville's fear of midnight wanderings, he bravely tries to warn Harry and Hermione when he hears that his bully, Malfoy, is going to catch them out after hours. His attempts to warn them, only get himself caught as well. He loses fifty points for Gryffindor as a result and gets a detention. Neville was made unpopular for his punishment, though he escaped the school-wide insults that Harry was given due to his being relatively unknown. For detention, Neville, Harry, Hermione, and Malfoy are sent with gamekeeper Hagrid into the Forbidden Forest. On their mission to find an injured unicorn, Neville is paired with Malfoy. Malfoy scares Neville into sending a signal for help and so switches places with Harry, as a result narrowly avoiding an encounter Lord Voldemort, who Harry and Malfoy meet shortly afterwards in the forest.
At the end of the year, when Harry, Ron and Hermione are once again planning on sneaking out after hours, Neville tries to stand up against them and stop them for the sake of Gryffindor House. Unfortunately, the trio are on an important mission and won't be stopped. Hermione puts the full Body-Bind curse on Neville, and they leave him immobile on the Common Room floor as they head out to the forbidden corridor. At the end of the year, when the House points are calculated to determine which House wins the House Cup, Headmaster Albus Dumbledore saves until the last minute giving large numbers of points to Ron, Hermione, and Harry for their efforts in stopping Voldemort from stealing the Philosopher's Stone (which had been hidden in the school). These points made Gryffindor's total equal to that of Slytherin. Last of all Dumbledore awards Neville ten points for the courage to stand up to his friends, his points being the ones to put Gryffindor in the lead and earn them the House Cup.
Neville was very impressed with Harry and Ron when they turned up to school this year by flying Ford Anglia. When Ron receives a Howler from his mother, Neville advises him from experience that it's better to open them than ignore them. The new Defence Against the Dark Arts professor, Gilderoy Lockhart, manages to awe Neville a little with his dark introduction to a cage full of Cornish Pixies. In the end Neville was perhaps right to be worried as once released the pixies seized him by the ears and left him hanging on the candelabra in the ceiling.
After the Chamber of Secrets was opened and Mrs Norris the cat and Colin Creevey had been attacked, Neville bought several items that would supposedly protect him (a large, green, smelly onion - possibly a Gurdyroot - a purple crystal and a newt tail) before the Gryffindors pointed out that as a Pure-Blood he was unlikely to be attacked. Neville's response is that everyone knows he's nearly a Squib, like Argus Filch, Mrs Norris' owner.
Neville had his first attempt at a duel when Lockhart formed a Duelling Club. His opponant was Justin Finch-Fletchley and neither of them seem to have managed to cast Expelliarmus as intended, as they were on the floor panting. Lockhart chooses them as a volunteer pair to teach them how to block spells, but Snape quickly steps in.
"Longbottom causes devastation with the simplest of spells. We'll be sending what's left of Finch-Fletchley up to the hospital wing in a matchbox." - Snape
When the time for the second years to choose their O.W.L.s Neville was sent reams of advice by letter from all the witches and wizards in his family, confusing him all the more with what he wanted to take. He went around asking people which subjects they thought sounded hard. Shortly afterwards it was Neville who found Harry's bed and possessions all thrown about in Ginny's attempt to find Tom Riddle's diary. On learning that despite the attacks they were still going to have end of year exams, Neville manages to accidentally Vanish the leg of his desk in Transfiguration.
When Harry Potter blew up his Aunt Marge he decided to run. When he accidentally managed to hail the Knight Bus rather than use his own name, he used Neville's. When Harry later sees Neville at Diagon Alley he chooses not to speak to him as he was being told off by his grandmother at the time for misplacing his booklist. While on the Hogwarts Express he enters the trio's compartment shortly before one of Azkaban's Dementors entered. He later explains the negative dementor experience so some of his fellow class mates. His third year at Hogwarts doesn't go so well having incidences breaking tea cups in Divination and not getting a hippogriff to bow to him. He also got into a bit of strife after he was unable to properly brew a potion the right color which angered Professor Snape, telling Neville that he'll feed it to his toad, Trevor. Later on in Defense Against the Dark Arts Class, Neville was the first to be chosen in Professor Remus Lupin's explanation on boggarts. His boggart transformed into Professor Severus Snape, as this was his biggest fear, with the counter boggart being Professor Snape in Neville's grandmother's clothing. After losing the passwords he had written down for Gryffindor Tower, Sirius Black managed to break into the castle. As this was Neville's fault (although not on purpose), he got a detention, his privileges to visit Hogsmeade were revoked and no-one was allowed to give any passwords to Neville. Because of this, a couple days later he recieved a howler from his Grandmother, where she shamed him for being a part of this family.
In the fourth book we discover that Neville's parents were sent to madness with the Cruciatus Curse by Voldemort' supporters naming Bartemius Crouch Jr. We start getting clues when he shivers at the Cruciatus Curse is performed on a spider by Mad-Eye Moody. Harry found out when he delved into Albus Dumbledore's memories in his Pensieve and saw Barty Crouch Jr, Bellatrix Lestrange, Rodolphus Lestrange and Rabastan Lestrange being sent to Azkaban.
Neville was one of 25 students invited by Hermione Granger to meet with her, Harry and Ron to discuss forming a secret Defence Against the Dark Arts group after new teacher Dolores Umbridge was refusing to teach them anything useful. He signs the parchment to join this group and to agree not to tell anyone what they were up to. This group became Dumbledore's Army, in which Neville excelled.
When Draco Malfoy makes a comment that Harry should be in the ward in St Mungo's for those who have received brain injuries by magic, pulling a grotesque face to demonstrate the state of those inside, Neville attempts to fight Malfoy for this insult to his parents (although from Malfoy's reaction he didn't know about their being in said ward). Harry manages to stop him, with the help of Ron
At Christmas Neville visits his parents, Frank and Alice Longbottom, with his grandmother. Just as they are leaving by a coincidence they run into Harry, Ron, Hermione and Ginny. They had been visiting Arthur Weasley in St Mungo's along with the other Weasleys and various Order members, when they had felt it prudent to leave the ward he was in quickly. They had left for a cup of tea on the fifth floor, but when they reached the fourth floor for Spell Damage they ran into their ex-Defence Against the Dark Arts professor, Gilderoy Lockhart who had lost his memory. They followed him and a Healer back into his ward and there they had seen Neville.
Neville is mortified to see his friends there, who he has never told about what happened to his mother and father. His grandmother believes he never told them because he was ashamed of them, but Neville denies it. The trio and Ginny watch as Alice goes up to Neville and tries to give him a present of an empty sweet wrapper, something she seems to have done many times before. His grandmother tells him to throw it away, but Neville pockets it. After they have left Harry tells them what he saw in Dumbledore's Pensieve the year before.
Later on Neville is supportive of Harry after he gives an interview in The Quibbler about his encounter with Voldemort and his Death Eaters the year before. He realises how hard it must have been to talk about it and comments that people should know what the Death Eaters are capable of. However he still seems unable to himself talk about what he knows they did to his family.
When Neville breaks into the Department of Mysteries along with Harry, Ron, Hermione, Ginny and Luna Lovegood, Harry and Neville are the last two standing when they try to stop Death Eaters from stealing the Prophecy. Neville's nose and wand had been broken by Antonin Dolohov, but he was still determined to help. Lucius Malfoy comments that Neville's death will not come as a shock to his grandmother as she is used to losing family members and Bellatrix Lestrange remarks that she has had the 'pleasure' of meeting his parents. She enjoyed mocking Neville about how she had tortured his mum and dad and uses the same curse on him as she had used on his mother. They were both rescued by the timely arrival of Dumbledore and the Order of the Phoenix.
When Harry sits with Neville, Ginny and Luna on the Hogwarts Express, he proudly calls them his friends when Romilda Vane implies that they aren't cool enough to be his friends. Neville and Luna were both disappointed to learn that Dumbledore's Army would not be meeting this year.
In Neville's last year at school Severus Snape had taken the role of Headmaster at Hogwarts after killing Albus Dumbledore. Death Eaters Amycus and Alecto Carrow were appointed as Defence Against the Dark Arts and Muggle Studies teachers, who were abusive and encouraged students to perform the Unforgivable Curses on others and to believe that Muggles are scum. Neville was outspoken against them. He was frequently punished, but his Pure-Blood status protected him from serious harm. He recalled Dumbledore's Army. He, Ginny and Luna had become the leaders whilst Harry, Ron and Hermione were on the run.
Neville had discovered that the Room of Requirement, which Dumbledore's Army had used as headquarters, could form a secret passageway to the Hog's Head in Hogsmeade when he hid there whilst starving. Unable to create food, the Room gave him a way to the pub, where Neville met Aberforth Dumbledore. Neville caused the Death Eaters enough trouble that eventually they attempted to kidnap his grandmother to hold her hostage against him. However she managed to overpower the Auror they had sent to catch her (John Dawlish) and sent him a letter saying how proud she was of him.
Later in the year, Harry, Ron and Hermione needed to get into Hogwarts to destroy the Horcrux hidden there. Aberforth sends the portrait of his sister, Ariana, to Neville in the Room, her portrait being the passage.
Portrayals within films
Neville is portrayed in all the films by Matthew Lewis.
Neville is described as round-faced.
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Magical accomplishments and skills
At first Neville displayed little magical ability. His grandmother feared he might even be a Squib. However he had magic enough to attend Hogwarts school. At first he mostly seemed to do badly in lessons, particularly in Potions and Transfiguration where he often caused accidents. However he displayed an aptitude for Herbology.
After Harry Potter taught him Defence Against the Dark Arts in the secret Dumbledore's Army in 1995, he became proficient at duelling and one of the quickest learners in the class. Neville studied to take N.E.W.T.s in Defence Against the Dark Arts, Herbology and Charms. He later became a Professor of Herbology.
- Neville owns a pet toad that frequently tries to escape from him, called Trevor.
- In 1991 in his first year at Hogwarts, Neville was sent a Remembrall by his grandmother.
- Neville owned a rare plant called Mimbulus Mimbletonia, which he took with him to Hogwarts in 1995.
- Up until his fifth year at Hogwarts Neville used his father's old wand. However in 1996 when he broke into the Department of Mysteries with some members of Dumbledore's Army, his wand was broken by Antonin Dolohov when he kicked Neville in the face and broke his nose.
- In 1996 Neville was one of the last of Ollivander's customers when he bought a new wand (cherry and unicorn hair).
Neville's parents were Frank and Alice Longbottom. They were popular Aurors who were tortured into insanity after Voldemort's first downfall in 1981. Death Eaters Bartemius Crouch Jr., Bellatrix Lestrange, Rodolphus Lestrange and Rabastan Lestrange had hoped to get Voldemort's whereabouts from them. They were all sent to Azkaban.
Neville was brought up by his grandmother, Augusta Longbottom. She was initially disappointed in her son's apparent lack of magical ability and forgetfulness. However when Neville helped Harry to break into the Department of Mysteries and fight Death Eaters, she at last became proud of him.
Neville has a great-uncle called Algie and a great-aunt called Enid. When Neville was young Algie tried to scare Neville into displaying magical talent. He even pushed Neville off of Blackpool pier where he nearly drowned. When Neville was eight years old he was hanging Neville from an upstairs window and accidentally dropped him when Enid offered him a meringue and he let go. Luckily Neville was able to magically bounce and as a reward Algie bought Trevor for Neville.
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In popular culture
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J. K. Rowling revealed that Neville ended up marrying Hannah Abbott (who became landlady of The Leaky Cauldron) and lives with her above the pub. In a PotterCast episode featuring J. K. Rowling she has said that Neville worked as an Auror for Kingsley Shacklebolt before becoming a Professor of Herbology at Hogwarts. She has also said that Neville would keep his magical Galleon from Dumbledore's Army which would impress his students.