Dumbledore's Army (or D.A. for short) is a fictional student organisation in J. K. Rowling's Harry Potter series that is founded by the main characters, Harry Potter, Ron Weasley and Hermione Granger, to stand up against the regime of Hogwarts High Inquisitor Dolores Umbridge, as well as to learn practical Defence Against the Dark Arts. It was founded in the fifth book, Harry Potter and the Order of the Phoenix.

In Harry Potter and the Order of the Phoenix, the new Defence Against the Dark Arts professor, Dolores Umbridge, chooses to teach only the basic theoretical principles of the subject in her classes instead of practical applications, due to Minister of Magic Cornelius Fudge's erroneous fear that Albus Dumbledore is preparing to assemble a student army to overthrow him. This theory-only approach is widely unpopular among the students, especially those characters like Harry, who are in their fifth year and have to take their O.W.L. exams on the subject later in the year. Harry also believes that lack of practical experience makes them more vulnerable to Lord Voldemort's forces, though the Ministry staunchly refuses to accept that Lord Voldemort has returned. This prompts Hermione to suggest founding a student group where Harry would teach practical Defence Against the Dark Arts.

After Dolores Umbridge learns about the project, she bans all unapproved student organisations, so meetings are secretly held in the Room of Requirement and announced to members through the use of enchanted fake Galleons created by Hermione. Cho Chang suggests the "Defence Association", shortened to "D.A.", as the official name for the group, but Ginny Weasley's suggestion of "Dumbledore's Army", to mock the Ministry's paranoia and to show the group's loyalty to Dumbledore, is chosen.

When Cho's friend Marietta Edgecombe betrays the group to Umbridge (Cho herself while under the influence of the truth potion Veritaserum in the film), Marietta is cursed with pimples on her face as a result of Hermione's casting a spell on the D.A. membership list. Later on, to prevent Harry's expulsion and the incrimination of other members, Dumbledore claims responsibility for organising the group, then escapes when Ministry officials attempt to arrest him. Though the D.A. stops meeting following these events, three members — Ginny, Neville and Luna — join Harry, Ron and Hermione in the battle in the Department of Mysteries towards the end of the fifth book. In Harry Potter and the Half-Blood Prince, Neville and Luna are distraught due to the fact that the D.A. no longer exists. When Hogwarts is invaded by Death Eaters, they are among the members who join the Order of the Phoenix in the ensuing battle.

In Harry Potter and the Deathly Hallows, with Harry, Ron and Hermione absent from Hogwarts, Neville, Ginny and Luna begin a covert rebellion against new headmaster Severus Snape by reactivating the D.A. However, Luna is abducted at Christmas and Ginny leaves during Easter, leaving Neville for a few weeks as the D.A.'s leader. Neville tells Harry that most of the D.A.'s activity ceased shortly after Michael Corner was tortured by Death Eater siblings Alecto and Amycus Carrow for trying to rescue a first-year boy from imprisonment. The group thereafter hide from the Death Eaters in the Room of Requirement, using a secret passage to the Hog's Head to find food. The D.A. believed that if Harry returned he'd lead them in a revolution against Snape and the Carrows and are disappointed when he initially refuses to let them help. Harry does lead an impromptu revolt, but only himself, Luna and Professors McGonagall, Sprout, Flitwick and Slughorn take part in it, with Harry and Luna taking out the Carrows, and the professors (rallied by McGonagall and Harry) driving off Snape. In the book's climax, the D.A. (alongside the Order of the Phoenix) plays an important role in the Battle of Hogwarts, giving Harry enough time to find the remaining Horcruxes.

In the play Harry Potter and the Cursed Child, an alternate timeline is created in which Voldemort has won the Battle of Hogwarts, killed Harry Potter and triumphed over the wizarding world. Ron and Hermione maintained the last remnants of the D.A. Twenty years later, they still wage hopeless resistance against the all-powerful Voldemort, clandestinely helped by Snape - in this reality still alive and still teaching at Hogwarts. Eventually, these remnants of the D.A. sacrifice themselves to cover the escape of Scorpius Malfoy and let him restore the timeline where Harry wins.

Lavender Brown is a Gryffindor student in Harry's year. She is a close friend of housemate Parvati Patil, and the two also seem to have a reasonably close relationship with Professor Trelawney, comforting and supporting her in her various crises. In Order of the Phoenix, she initially believes the Ministry's smear campaign against Harry, but is among the original members of Dumbledore's Army. In Half-Blood Prince, Lavender becomes Ron's first girlfriend for several months; he relishes the opportunity to make Hermione jealous and prove that he can "snog" (kiss) people whenever he wants. It becomes increasingly evident that Ron is not particularly enamoured with Lavender and actually finds her irritating. Lavender becomes jealous of Ron's friendship with Hermione, and finally splits up with him when she sees them leaving Harry's dormitory together, as she is under the impression that they had been alone together, not realising Harry was there under his invisibility cloak. In Deathly Hallows, during the Battle of Hogwarts, Lavender is attacked by Fenrir Greyback, but is saved by a crystal ball hurled by Professor Trelawney, ultimately surviving the battle.

Kathleen Cauley portrayed Lavender in a non-speaking cameo of Harry Potter and the Chamber of Secrets. Jennifer Smith portrayed Lavender in a brief, non-speaking role in Prisoner of Azkaban. Jessie Cave played the character in a larger role from Half-Blood Prince onwards. Unlike in the book, Lavender dies in Deathly Hallows – Part 2, in which Greyback successfully kills her.

Cho Chang is a Ravenclaw student one year above Harry, and plays Seeker for the Ravenclaw Quidditch team. She is best known for being Harry's first love interest, is described as being "very pretty" with long dark hair and is frequently accompanied by a group of giggling Ravenclaw girls. In Goblet of Fire, Harry's crush on Cho intensifies and he works up the courage to ask her out to the Yule Ball, but Cho apologises and replies that she had previously accepted Cedric Diggory's offer. Nonetheless, Cho is still kind to Harry, much to his relief, and she refuses to wear one of Malfoy's "Potter Stinks" badges. She and Cedric maintain their relationship until his murder by Peter Pettigrew.

Cho is one of the first students to believe Harry's declaration of Voldemort's return in Order of the Phoenix, and when invited by Hermione to join the D.A., she joins because she is determined to fight against Voldemort and avenge Cedric's murder. Cho initiates a kiss with Harry after the last D.A. session before the Christmas holidays; much to Ron's amusement, Harry describes the kiss as "wet," but then explains that Cho was crying. Harry and Cho go out on a date on Valentine's Day, but her sustained grief over Cedric's death, her jealousy over Harry's friendship with Hermione, and Harry's lack of knowledge about girls all make for a miserable experience. Their relationship ends when the D.A. is exposed following Marietta Edgecombe's betrayal of the group to Umbridge. Cho defends her friend's actions by saying that Marietta simply made a mistake. On the train back to King's Cross, Ginny reveals that Cho was now seeing Michael Corner.

In the series finale, Cho demonstrates her loyalty to Hogwarts when she returns to join other D.A. members in hiding in the Room of Requirement prior to engaging in the Battle of Hogwarts; Harry and Cho, united by a common cause, appear on amicable and friendly terms. She shares with Harry the little information known about Ravenclaw's diadem (one of Voldemort's Horcruxes). Rowling said during an October 2007 book signing that Cho marries a Muggle.^[3]

Cho was played by Scottish actress Katie Leung in the film series starting from the character's debut in Harry Potter and the Goblet of Fire. In the Order of the Phoenix film, she exposes Dumbledore's Army to Umbridge while under the influence of Veritaserum,^[4] whereas in the novel the betrayal is willingly carried out by Marietta Edgecombe.

Colin and Dennis Creevey are two Muggle-born brothers sorted into Gryffindor; Colin is one year younger than Harry, and Dennis is two years younger than Colin. Both are delighted at the discovery that they are wizards, and are star-struck by Harry. Colin takes photographs of memorable people, objects and events to send home to his family. Ironically, Colin's camera later proves to be a lifesaver when he attempts to take a picture of the basilisk, and the camera lens shields him from the creature's direct and fatal eye contact, and Colin is only Petrified. Despite being too young to take part in the Battle of Hogwarts, Colin sneaks back into the castle to participate, and dies in combat.

Hugh Mitchell played Colin in the film version of Chamber of Secrets, and voiced the character in the Order of the Phoenix video game. Dennis never appeared in any of the films. In the Goblet of Fire and subsequent films, the roles of Colin and Dennis were morphed into a second-year character named Nigel Wolpert, portrayed by William Melling.

Seamus Finnigan is an Irish Gryffindor student in Harry's year who is described as having sandy hair. His mother is a witch and his father a Muggle, who only found out his wife's secret after their marriage. His best friend is Dean Thomas, who he is housemates with. In Order of the Phoenix, Seamus is initially influenced by the Ministry's smear campaign against Harry, and his mother nearly prevents him from returning to Hogwarts. However, he later realises his mistake, offers his apologies to Harry, and becomes a late addition to the D.A. In Half-Blood Prince, Seamus refuses to allow his mother to take him home before Dumbledore's funeral. In Deathly Hallows, it is stated that Seamus is taking shelter in the Room of Requirement along with several D.A. members; his face is bruised so badly after being punished by the Carrows that Harry initially fails to recognise him until he speaks. During the battle, he, Luna, and Ernie help Harry fight the Dementors by conjuring their respective Patronuses; Seamus' takes the form of a fox. He is last seen entering the Great Hall to take part in the final stage of the battle, when Harry shields him and Hannah Abbott from one of Voldemort's curses.

Devon Murray played Seamus in the Harry Potter film series and voiced the character in the eighth game. He has appeared in all eight films, one of the few characters to do so.

Neville Longbottom is a pure-blood Gryffindor student in Harry's year, described as round-faced and "short and plump and blond".^[5] His parents, Frank and Alice Longbottom, were prominent Aurors and Order of the Phoenix members until they were tortured into insanity, through the use of the Cruciatus Curse, by a group of Death Eaters led by Bellatrix Lestrange. Neville was subsequently raised by his paternal grandmother, Augusta. Throughout the series, he is often portrayed as a bumbling, disorganised character and a rather mediocre student, though he is highly gifted at Herbology. Neville plays a minor role in the first four books, but Rowling wanted him to perform an act of bravery in Philosopher's Stone, in which Neville "finds true moral courage in standing up to his closest friends — the people who are on his side" towards the climax.^[6]

According to Rowling, Order of the Phoenix "was a real turning point for Neville" due to the central role he played in the book.^[7] His magical abilities improve dramatically during D.A. meetings. Neville participates in the battle in the Department of Mysteries, in which he accidentally breaks the prophecy about Harry and Voldemort.^[8] Dumbledore, to whom it was originally made, explains that it concerned "the Chosen One", a wizard who would have the power to vanquish Voldemort and who would be born "as the seventh month dies" to "parents who have defied the Dark Lord thrice"; thus could refer to either Neville, who was born on 30 July 1980, or Harry, who was born a day later.^[9] This means that Neville could easily have had Harry's fate, had Voldemort chosen to target him instead of Harry. Neville is also one of the few D.A. members to participate in the battle of the Astronomy Tower in the climax of Half-Blood Prince.

In Deathly Hallows, with Hogwarts at the mercy of new headmaster Severus Snape and Death Eater siblings Alecto and Amycus Carrow, Neville re-forms the D.A. with Ginny and Luna, and spends much of his seventh year as the resistance's leader, helping students who are tormented under the new regime. He is punished for his actions by the Carrows and is forced to go into hiding in the Room of Requirement to avoid Azkaban or death. In the Battle of Hogwarts Neville openly defies Voldemort, so the Dark Lord immobilises him, places the Sorting Hat on his head and sets it on fire. Neville later breaks free of the curse, pulls Godric Gryffindor's sword from the Sorting Hat, and uses it to decapitate Nagini (on Harry's orders), thus destroying the final Horcrux. In the ensuing conflict, he assists Ron in defeating werewolf Fenrir Greyback. In the epilogue of Deathly Hallows, Neville is Herbology professor at Hogwarts and still good friends with the Potter and Weasley families. Post-Deathly Hallows, Rowling revealed that Neville married Hannah Abbott, now the landlady of The Leaky Cauldron, and his students think it is particularly cool that he lives above the pub.^[10][11][12]

In the alternate timeline created in The Cursed Child, Neville was killed by Cedric Diggory at the battle of Hogwarts, which resulted in Voldemort's triumph. These events are undone by Scorpius Malfoy, allowing history to continue as it originally did.

Neville was played by Yorkshire-born actor Matthew Lewis in the Harry Potter film series. He has appeared in all eight films. He reprised the role for the videogame Lego Dimensions.

IGN listed Neville as their sixth top Harry Potter character, calling him the "quintessential dimwit-turned-hero".^[13] In NextMovie.com's Harry Potter Mega Poll, Neville was voted as the top character that should get a spin-off movie or book.^[14] Empire listed Neville as their 8th favourite Harry Potter character.^[15]

Luna Lovegood is a Ravenclaw student one year younger than Harry. She is described as having straggly waist-length dirty blond hair, grey eyes and a "permanently surprised look". Rowling has often said that Luna is the "anti-Hermione", as Hermione is "inflexible and logical," as opposed to Luna, who would "believe 10 impossible things before breakfast."^[16] Her father, Xenophilius Lovegood, is the editor-in-chief of The Quibbler, a strange magazine claiming supposedly untrue things Luna and her father believe. When Luna was 9 years old, her mother Pandora died while performing a spell experiment, the particular one having gone, as Luna stated, "horribly wrong". Luna witnessed the incident, which enabled her to see Thestrals. Luna is socially isolated at school, and is given the nickname "Loony" Lovegood for her bizarre personality, but she appears to have the rare quality of caring little about what others think of her, although she sometimes gets incensed when her beliefs are challenged.

In Order of the Phoenix, Luna and her father, Xenophilius Lovegood, are among the few who believe Harry and Dumbledore when they state that Voldemort has returned. She later becomes a member of Dumbledore's Army. Later in the book, she joins Harry, Ron, Hermione, Ginny, and Neville in the conflict with Death Eaters in the Department of Mysteries. In Half-Blood Prince, Luna remains close friends with Harry and the others. Harry later invites Luna to Professor Slughorn's Christmas party as his plus one. She also does the Quidditch commentary for Gryffindor's game against Hufflepuff, a scene that Rowling particularly enjoyed writing, calling it "blinding inspiration".^[17] Later, when Death Eaters attack Hogwarts, Luna, Ginny, and Neville are the sole D.A. members who answer the call to protect Hogwarts.

In Deathly Hallows, Luna and her father attend Bill Weasley and Fleur Delacour's wedding at the Burrow. She returns to Hogwarts for her sixth year, where she and Ginny help Neville secretly revive the D.A. to oppose Snape's regime as Hogwarts headmaster. Later in the book, Harry, Ron, and Hermione learn that Luna has been kidnapped by Death Eaters in an effort to prevent her father from publishing an article in support of Harry in the Quibbler. However, she is later rescued, along with the recently captured Harry, Ron, and Hermione, by Dobby, who takes them to safety at Shell Cottage. When Harry returns to Hogwarts in search of Ravenclaw's diadem, Luna helps him enter the Ravenclaw common room to view a replica of it, and actively participates in the Battle of Hogwarts. Rowling revealed that, after Hogwarts, Luna pursues a career that is "the wizarding equivalent" of a naturalist.^[18] She marries a fellow naturalist named Rolf Scamander, the grandson of Newt Scamander, and has twin boys, Lorcan and Lysander.^[19][20]

Irish actress Evanna Lynch portrayed Luna in the last four Harry Potter films, and reprised the role for StarKid productions' A Very Potter Senior Year.^[21] She also voiced the character for Lego Dimensions.

IGN listed Luna as its 12th top Harry Potter character, saying that her looniness made her a "delight".^[13] Empire listed Luna as its 10th favourite Harry Potter character in "The 25 Greatest Harry Potter Characters".^[22]

Parvati Patil is a Gryffindor student in Harry's year and the twin sister of Ravenclaw student Padma Patil. Her best friend is Lavender Brown; they are particularly fond of Trelawney's Divination class, and share many common interests. In Goblet of Fire, when Harry needs a date to the Yule Ball, he asks Parvati and she accepts. However, her evening is a disappointment as Harry spends the evening jealously preoccupied over Cho Chang's date with Cedric Diggory and disdains dancing with Parvati; she eventually abandons him to dance with a Beauxbatons boy whom she then later meets in Hogsmeade. In her fifth year, Parvati joins Dumbledore's Army along with her sister. In Half-Blood Prince, the twins are almost removed from Hogwarts by their parents, and ultimately do return home after Dumbledore's death. However, the Patil twins return to their seventh year at Hogwarts, and participate in the Battle of Hogwarts.

The Patils' names and appearance in the films imply that they are of Indian descent. Patil is a common Marathi surname in the state of Maharashtra, India. Rowling originally intended the twins' first names to begin with "Ma", and on her classlist from Harry Potter and Me, their last name was spelled as Patel. Parvati means 'daughter of the mountains', an alternate name for the Hindu goddess Durga, the goddess of strength, while Padma is the Sanskrit word for lotus, an alternate name for the Hindu goddess Lakshmi, the goddess of prosperity. Together, they form a part of the trinity of the Hindu goddesses.

Parvati was portrayed by Sitara Shah in Prisoner of Azkaban. Shefali Chowdhury took over the part for Goblet of Fire, along with the film and game versions of Order of the Phoenix and Half-Blood Prince.

Dean Thomas is a Gryffindor student in Harry's year, and is Seamus Finnigan's best friend. He is a Half-blood: his mother is a Muggle and his father was a pure blood wizard who kept his blood status a secret. Dean's father left his family when Dean was very young in an attempt to protect them against the Death Eaters, and was slain when he refused to join them. Dean originally prefers football (soccer) over Quidditch, and has a poster of the West Ham football team in his and Harry's dormitory. Dean was subsequently raised by his mother and stepfather, and has several half-brothers and sisters.^[23] Dean was named "Gary" in the original drafts of Philosopher's Stone.^[24] Rowling omitted his physical description ("a black boy taller than Ron") from the British version of the book following her editor's request to reduce the length of the chapter, but it was included in the American edition. His backstory was originally expanded in Chamber of Secrets, but she ultimately cut it due to her inability to work it into the storyline.^[25]

In Order of the Phoenix, Dean joins the D.A. and also believes Harry and Dumbledore when they insist that Voldemort has returned; but, when Harry and Seamus engage in a heated row over the Daily Prophet's allegations that Harry had merely fabricated the story, Dean refuses to take sides. At the end of the term, he begins seeing Ginny Weasley. The two of them are still dating in Half-Blood Prince, but Ginny thinks that Dean is being pushy and overprotective, which leads to the fight that ends their relationship. Dean temporarily fills in for Katie Bell on the Gryffindor Quidditch team after she is hospitalised. Dean's role is expanded in Deathly Hallows. Unable to prove that he is actually a Half-blood, he does not return to Hogwarts and goes on the run from the Ministry, who are rounding up Muggle-borns upon Voldemort's orders. Harry, Ron, and Hermione first come across him during their mission as they eavesdrop on his conversation with fellow runaways Ted Tonks, Dirk Cresswell, and the goblins Griphook and Gornuk. Snatchers soon viciously attack the group; Dean and Griphook are the lone survivors but are captured along with Harry, Ron, and Hermione and taken to Malfoy Manor. They are all rescued by Dobby, who transports them to Bill and Fleur's Shell Cottage for protection. Dean returns to Hogwarts towards the end of the book and fights in the Battle of Hogwarts.

Alfred Enoch played Dean in the Harry Potter film series and voiced the character in the Order of the Phoenix and Deathly Hallows: Part 1 video game.

Fred Weasley and George Weasley are the fun-loving, troublemaking twins of the Weasley family. Born on April Fools' Day, the two work together making pranks and are addressed as a single unit as opposed to two individual people. They are so similar that even their parents often have a difficult time telling the two apart. They first appear in Philosopher's Stone as third years and were always said to be the school clowns. Despite their poor results in their O.W.L. exams, the twins are intelligent and proficient wizards capable of sophisticated magic. In addition, they serve as Beaters for the Gryffindor Quidditch team.

The pair often come to Harry's assistance throughout the series; in Chamber of Secrets, they and Ron help him escape his house arrest from Privet Drive in a flying Muggle car, and give Harry the Marauder's Map during his third year. In Goblet of Fire, they begin selling novelties under the name "Weasleys' Wizard Wheezes". Though their mother wants them to work for the Ministry of Magic, the twins aspire to own a joke shop, and Harry provides their start-up capital by donating his winnings from the Triwizard Tournament. In Order of the Phoenix, the twins, like Harry, are permanently banned from Quidditch after a postmatch brawl with Malfoy. They join the D.A. and lead a student uprising against Umbridge towards the end of the book, leaving Hogwarts in dramatic fashion before the term ends. In Half-Blood Prince, Fred and George continue to run their joke shop despite the unrest in Diagon Alley.

In Deathly Hallows, the twins serve as two of Harry's six decoys when he escapes Privet Drive. George's ear is permanently severed by a stray Sectumsempra curse from Severus Snape, who was actually aiming at a Death Eater. Meanwhile, the twins are forced to abandon their shop due to the Death Eater-controlled Ministry of Magic's surveillance of the Weasley family, and instead operate another owl-order business out of their Great-Aunt Muriel's house. During this time, one of the twins, speculated to be Fred,^[26] shows up in the pirate radio station Potterwatch as "Rapier".^[27] The twins return to participate in the Battle of Hogwarts, during which Fred is killed in an explosion. Rowling said in an MSNBC interview that she always knew Fred would be the twin who would die, though she could not specify a particular reason.^[28] She stated in a web chat after the release of Deathly Hallows that George never fully gets over Fred's death, but succeeds in turning Weasleys' Wizarding Wheezes into a "money spinner" with Ron, who eventually quits to become an Auror.^[29][30] Rowling also revealed that, by the time of the epilogue of Deathly Hallows, George is married to Angelina Johnson and has two children, Fred and Roxanne.^[31]

Identical twin actors James and Oliver Phelps played Fred and George respectively in the Harry Potter film series.

Fred and George were listed by IGN as eleventh top Harry Potter characters, saying that "taking umbrage at Umbridge and leaving Hogwarts with a bang in Order of the Phoenix showed us that these two weren't just goofy side splitters; they were brave and valiant freedom fighters".^[13]

The goal of Dumbledore's Army inspired actor/comedian Andrew Slack, a Harry Potter fan, to create a group called Harry Potter Alliance to highlight the crisis in Sudan and social inequalities.^[32] In an interview, Slack compared Harry and the D.A. to Darfur, claiming, "With both the Ministry of Magic and the Daily Prophet (the Wizarding World's mainstream news source) in denial that Voldemort has returned and evil is afoot, Harry and his underground rebel group, 'Dumbledore's Army,' work with the adult group, 'The Order of the Phoenix,' to awake the world into peace."^[33]