Harry Potter
The changes come about in the first book(which is never renamed
The Philosopher's Stone in the US). Harry's parents are mentioned to have stolen the Philosopher's Stone. Harry later finds the small stone in the bag of gold his parent's left him and it is implied to be why the Potters became extremely rich. Hermione is in Ravenclaw and is mentioned to have a younger sister. Dean Thomas is given more of a backstory, his biological father was a wizard killed for refusing to join Voldemort, but Dean's mother just thought he abandoned her.
Chamber of Secrets carries more foreshadowing(which it almost did but the editor told her to cut it out and Rowling was not yet popular enough to ignore this, here she is). This prevents
Half-Blood Prince from being Exposition heavy. There is an extra chapter called "Malfoy and Nott" in which there is a meeting between said characters. Theodore Nott comes with his father to Malfoy Manor to discuss whatever Death Eaters discuss, only for the boys to get kicked out of the discussion and have one of their own about Voldemort, the Death Eaters and The Boy Who Lived. Draco is actually shown respecting someone as his equal, because they were just as good students as each other and came from "elite" families. The book also revealed Nearly Headless Nick's backstory told in rhyme. Penelope Clearwater is also introduced as a fifth year.
Goblet of Fire contains a female character named Mafalda(not the Ministry of Magic employee who doesn't exist ITTL). She is the "black Sheep cousin" of the Weasleys, the daughter of the accountant squib relative Ron mentioned to Harry in
Harry Potter and the Philosopher's Stone: extremely badly-behaved, unpleasant to be around, nosy and loose-tongued, and to top it off, being sorted into Slytherin. She was the first real rival to Hermione. She also desires to be a reporter. Rowling initially had trouble introducing her but it was decided she was a student of Beauxbatons(She takes the role of OTL Rita Skeeter as a result).
In
Order of the Phoenix, Anthony Goldstein is introduced as a Hufflepuff.
In
Deathly Hallows, a subplot involving Ice cream parlour owner Florean Fortescue, who is kidnapped and then rescued by Harry, Hermione and Ron, providing them clues about the Elder Wand and Ravenclaw Diadem(was cut OTL but explains why the shop closing and Fortescue's kidnapping get so much attention in
Half-Blood Prince). Rolf Scamander(Luna's Future husband) appears in the book and is the one to explain
The Tale of the Three Brothers. The epilogue contains details of the lives of the main trio(while all had children it receives less attention). The Epilogue also revealed Dudley had a muggle-born wizard child for added irony. Harry and Hermione end up getting together.
Harry Potter and the Curse Child was written by JK Rowling and includes much of the information later mentioned by Rowling. Rather than involving time travel, it involves a new threat, a witch called Delphi with no connection to Voldemort. Harry and Hermione both have affairs that form part of the plot. Rowling's behavior in general is different. She does not reveal facts unless asked and responds vaguely("There are many Jewish wizards at Hogwarts"). She also admits she gets birth dates and numbers mixed up and doesn't answer question like those. She also revealed Nagini was never a woman. Hermione is not retconned as being black though Rowling admits to having no problem if she is cast as a black actress.
Prior to Films
Universal Studios Shop Promoting Nintendo's Harry Potter Video Game Series(Fittingly located between the Wizarding World and Nintendo World).
Before the Films, Nintendo was interested in developing a video game adaptation of the original book, initially aiming to provide a very British-oriented take in line with J.K. Rowling's wishes. Nintendo of Japan began to drift away from the British-orientation and brought it towards a Japanese friendly version that took considerable liberties from the source material, turning it into what became known as "Japanese Harry Potter" similar to the Animated "American Harry Potter" version. The Japanese Harry Potter series benefitted from being allowed to diverge from the source material and so gameplay and fun was prioritized, turning the Boy Wizard into a popular Nintendo series in its own right. Nintendo's Harry Potter later appeared in
Super Smash Bros.
Bruce Springsteen wrote the song "I'll Stand By You Always" a ballad between 1998 and 2000, which he was inspired to write after reading the books to his son Sam. Bruce made the song available to Director Terry Gilliam and included in the first film.
Films
View attachment 624044
Fanart of the Characters from the Animated Harry Potter series, by Stephen Byrne on Instagram.
Terry Gilliam was handpicked by Rowling to direct
Harry Potter and the Philosopher's Stone. Steven Spielberg was also considered but he wanted the film to be animated in CG. Steven Spielberg would go onto make his animated
Harry Potter and the Sorcerer's Stone film with Haley Joel Osment as Harry. Spielberg made only the first film before handing it off to other directors. it is sometimes called American Harry Potter. The Animated Severus Snape was voiced by Christopher Lee. Tim Roth was cast in the Live Action film(OTL he was playing General Thade in Tim Burton's
Planet of the Apes, which does not exist ITTL, however he does not play Snape so as to keep Alan Rickman's excellent performance.). Rowling lifted her ban on British actors and so Robin Williams played Hagrid), Rosie O'Donnell played Molly Weasley, and Drew Barrymore also had a role. The character of Peeves appears in the film, played by Rik Mayall. The Movie is generally more fantastical and include Snape's trial to get the Philosopher's stone(while the scene could have been boring as its a puzzle involving which potions to drink in which order, Gilliam made it fun by having the potions have interesting effects on the drinkers).
For
Chamber of Secrets, Terry Gilliam returned to direct. Frank Oz was offered to direct but had no interest, though he did provide the practical effects for Dobby the House elf. Madam Hooch mad a return( Zoe Wanamaker being paid more than OTL and so taking the role). Hugh Grant played Gildreoy Lockhart. The film included the Deathday party scene, Hermione getting a get well soon card from Lockhart, and Ginny seeing Harry with the diary.
Terry Gilliam did not return to direct
Prisoner of Azkaban, Kenneth Branagh was offered to direct but declined as he would be directing his ex-wife Emma Thompson. Guillermo del Toro directed the film instead(OTL he declined as the movie's world didn't fit his darker perspective of the books, Terry Gilliam made the movies a bit darker than OTL so he accepts). Ian McKellen took over for Dumbledore after Richard Harris's passing(Yes he was seriously considered and declined because it wouldn't have felt right. Harris hated McKellen until his dying breath because he had wanted to play Gandalf and McKellen stole that role, considering Dumbledore to be the lesser of the roles. Here Harris never said any of that since he played Gandalf in the Hobbit first and was not replaced in the role by McKellen until after he had already died. McKellen thus jumps directly into the Dumbledore role after the Gandalf role). Fan theories abound that Gandalf eventually changed his named Dumbledore and is in fact immortal. Even more jokes are made about characters from the Harry Potter and Lord of the rings franchises meeting. Peter O'Toole was considered for the role but could not carry out the action scenes the role required in the later books. O'Toole did however voice Dumbledore in the Animated films. The new film also goes into detail about why Harry's patronus is a stag.
Guillermo Del Toro returned to direct
Harry Potter and the Goblet of Fire. Percy Weasley appeared in the film(Chris Rankin getting a five movie deal instead of the four he got). Henry Cavill played Cedric Diggory(OTL Potter fans campaigned Cavill for the role but he lost it to Robert Pattinson and funny enough was also up or the role of Edward Cullen in
Twilight as the author Stephanie Meyer actually pictured him in the role when writing. He once again lost the role to Robert Pattinson. Here
Twilight does not exist so Cavill got at least one over one Cullen). The Band Franz Ferdinand were huge fans of the series and appeared to play the Weird Systers, along with Jarvis Cocker of Pulp(OTL this did not happen due to a law suit by the Canadian folk rock band Wyrd Sisters. Cocker made a full album with guests such as Iggy Pop being included.
In the film itself, Winky the Elf appears, as does the lengthy plot between the Weasley twins and Ludo Bagman, played by Maritn Landham. There is an added scene in which Tom Felton is changed back to normal after being turned into a ferret and is naked, causing him to run off in embarassment, to the delight of fan girls.
For
Order of the Phoenix, Del Toro returned to direct(pushing back
Hellboy II: The Golden Army). Bellatrix Lestrange is still played by Helena Bonham Carter. Anna Friel played Nymphadora Tonks. Saoirse Ronan played Luna. There is a cameo from English footballer Theo Walcott. The St.Mungo's scene is included, complete with Hugh Grant reprising his role as Gilderoy Lockhart. Sirius's death scene is as it happens in the book. Radcliffe's performance caused multiple actors to cry on set.
Del Toro returned to direct
Half Blood Prince. Bob Hoskins played Horace Slughorn. Kevin McKidd played Fenrir Greyback. Naomi Watts played Narcissa Malfoy. All the Voldemort flashbacks from the book are included. The appearance of the Carrow twins tied into Draco Malfoy traveling between the Vanishing Cabinet in Hogwarts and the one in Borgin and Burkes.
Del Toro returned to direct the last two installments. John Williams returned to do the score. Billy Connolly played Florean Fortescue in a minor role. Kate Winslet played the Grey Lady. Crabbe is killed in the same way as in the book, a victim of Fiendfyre(this is due to the actor playing Crabbe not beinf caught with Marijuana). In the final scene, Draco tossed his wand to Harry after he revealed himself to be alive, allowing him to fight Voldemort.
Post Films
After the films the series lived on through
Pottermore. The book
Fantastic Beasts and Where to Find them introduced the Lethifold, which appeared briefly attacking Harry in actual films. There was a Michael Jackson made
Harry Potter Musical made(Along with Starkid's
A Very Potter Musical now having much more to make fun of thanks to Michael Jackson's inclusion).
Following the release of
Fantastic Beasts and Where to find them. A Second film was released
Dumbledore and Grindelwald. Which focused solely on the relationship between the two Wizards, featuring no characters from
Fantastic Beasts(Johnny Depp never went through the Amber Heard controversy and they divorced earlier so no one is uncomfortable with Depp's presence, though he does not advertise the film at Comic Con
).The film concludes with Grindelwald's defeat in 1945. The next film is planned to be
Marauders. A film about the titular group with Martin Freeman playing Peter Pettigrew and Tom Hiddleston playing a young Snape. It concerns the group going on an adventure as Voldemort is beginning to rise.