Kate Winslet was first considered for and reportedly offered the role of Helena Ravenclaw. The role was rejected by her agent before she was able to consider it, believing that Winslet would not want to "follow suit with every other actor in Britain by being a part of Harry Potter". The role subsequently went to Kelly Macdonald.
When Harry revealed that he was still alive in the Hogwarts courtyard, Draco was meant to initially break ranks with the Death Eaters and throw Harry his wand. The scene was filmed, but not included in the final edit.
According to J.K. Rowling, the battle of Hogwarts was fought on 2 May 1998. Victoire Weasley (Bill and Fleur's eldest daughter) seen at the background in the epilogue has the same birth date, 2 years later, her name meaning "victory" in French.
The fight between McGonagall and Snape was considered to be changed into Potter against Snape instead. The idea was scrapped by J.K. Rowling, who insisted that the duel should involve the same characters as them in the novel, as she saw it as a key moment for Maggie Smith's character.
It was reported that a huge blaze wrecked the Hogwarts set after a battle scene went spectacularly wrong. According to the report, explosives used in action sequences set light to scenery for the wizardry school, and that firefighters battled for 40 minutes to bring the flames under control but the set - centerpiece for the film's Battle of Hogwarts climax - was left badly damaged. It was later confirmed that the fire was greatly exaggerated, and that the set that had been damaged was going to need be rebuilt anyway for use in another scene. Some actors were still filming at the studio but none of the movie's biggest stars - Daniel Radcliffe (Harry), Emma Watson (Hermione) or Rupert Grint (Ron Weasley) - were involved. No one was injured.
Upon release, it set the record of the highest-grossing opening weekend ever, with $169.2M (previously held by The Dark Knight (2008), which earned $158.4M in its opening weekend). The record was broken again ten months later by The Avengers (2012), which earned $207.4M in its first three days.
Six of the eight 'Harry Potter' movies have been nominated for an Oscar totaling twelve nominations in the franchise. This final film in the series was nominated for three Academy Awards in 2012 and since the franchise had never won an Oscar, there was some expectation that this movie would do it. When the film failed to win any of them, it became film history that the 'Harry Potter' series never won an Oscar.
Every wand seen in any film in the franchise was created on-site. Taking the lead from descriptions in the books, each wand was 13-15 inches long and created specifically for each character. No two wands were alike.
Harry's lightning bolt scar was applied by make-up teams approximately 5,800 times by the end of the series. Daniel Radcliffe had the scar applied 2,000 times while the rest were applied to stunt doubles and stand-ins.
This is the only entry in the series not to feature an arrangement of John Williams' "Hedwig's Theme" playing over either the Warner Bros. logo or the title at the beginning of the film. The theme is, however, used several times throughout the rest of the movie, including an extended performance at the beginning of the end credits.
This movie, the last in the 'Harry Potter' franchise, has the equal highest number of Academy Award nominations by a 'Harry Potter' movie totaling to three. The other series entry to do this was the first film in the franchise, Harry Potter and the Sorcerer's Stone (2001). This is the only 'Harry Potter' movie to be Oscar nominated for the Best Make-Up Academy Award.
The trivia items below may give away important plot points.
Not long after Alan Rickman started to play Severus Snape, J.K. Rowling told him some character secrets about Snape that would not be otherwise revealed until the last book. Most significantly, Rickman was one of the very few people other than Rowling to know (years ahead of the last book's publication) that Snape had been in love with Lily Evans (later Potter) when they were students at Hogwarts, and both Snape's protection of and antagonism toward Harry came from that. Rowling said that she shared this information with Rickman because "he needed to understand, I think, and does completely understand and did completely understand where this bitterness towards this boy, who's living proof of [Lily's] preference for another man, came from." According to Rickman, the directors prior to the publication of the last book were not privy to the information of Snape's true character either, and he had to ask them to defer to him on the portrayal of Snape, whether or not they understood why.
According to J.K. Rowling, one of the few characters that was sure to survive the entire series was Hagrid. She had always had an image of a grieving Hagrid carrying a deceased Harry into Hogwarts, which was fitting since it was Hagrid who had also introduced Harry into the wizarding world.
At the end of the film, Harry has two sons and a daughter, one of whom he addresses as "Albus Severus Potter." The older one, never addressed by name, is James Sirius Potter (named after Harry's father and godfather). The girl's name is Lily Luna Potter (named after Harry's mother and good friend Luna Lovegood).
Although all of the films except Harry Potter and the Sorcerer's Stone (2001) have had a customized version of the Warner Bros. logo, this one has a scene (a replay from the previous film of Voldemort robbing Dumbledore's grave) before the studio logo - the first time this has been done for a studio-made Hollywood film in over 75 years.
Although Harry Potter (Daniel Radcliffe) does in fact survive in the end, this is the only Harry Potter movie in which Harry himself does not deliver the final line (his son Albus Severus Potter does instead). It should also be noted that in the end of the actual book, Harry does in fact deliver the last spoken line, although the remaining text is narration.
The script was originally written, like the book, to include Draco Malfoy's bully friends, Crabbe and Goyle. As in the book, Crabbe was to be killed in a climactic battle. Jamie Waylett's arrest and conviction on drug charges, however, forced the filmmakers to change this plan. Crabbe was written out of the script, with Goyle being killed in his place. Another Slytherin character Blaise Zabini (portrayed by Louis Cordice) takes Goyle's place from the book.
Both Emma Watson and Rupert Grint have stated in several separate interviews, that filming their much awaited on-screen kiss was an "absolutely horrible" experience, due to Emma's admission of Rupert being "like a brother." It took only six takes to complete; whereas the kiss between Harry & Ginny took around ten, Ron & Lavender approx. 15, and Harry & Cho took over 30 takes, by comparison.
The character Fenrir Greyback (Dave Legeno) is a reference to Fenris the Wolf in Nordic mythology. In the mythology, Fenris was part of the Ragnarok battle and was foretold to be killed by Vidar in retaliation to the murder of Odin. The film shares the similarities: Fenrir was also part of the attack at Hogwarts akin to Ragnarok; and one of Hermione's spells caused him to fall to his death. However, in the novel, Ron was supposedly the one indirectly killing him thus matching the role of Vidar killing Fenris.
J.K. Rowling initially considered having Arthur or Ron as the Weasley casualty but decided to give reprieve to both as they form an integral part of the series. She ultimately settled on having Fred killed as it serves two purposes: to give a sense of loss for George and the payoff of Percy's rivalry against his Ministry's arch-rival Rookwood (who was revealed to be a Death Eater).
In the book, Snape's (Alan Rickman) death originally takes place at the Shrieking Shack, but art directors suggested and moved the location (with J.K. Rowling's agreement) to the boathouse in order to make it more dramatic and poignant. One of the art directors, Andrew Ackland-Snow added, "We wanted to get him out from, not a conventional interior, but from that kind of box, to do it in a more dramatic atmosphere."
Some time before the final book was published, Daniel Radcliffe asked writer J.K. Rowling whether his character Harry would die at the end. After a silence, Rowling gave him the very cryptic answer "You get a death scene".
By her own admission, killing off Remus Lupin was one of the hardest decisions that J.K. Rowling had to make while writing the books. She felt that, in order to show that war sometimes demands impossible sacrifices, someone important had to die. She finally chose both Lupin and Tonks as the casualties, as it made their infant son Teddy an orphan, which closely mirrored infant Harry losing his parents in the previous war. In the book, Harry appropriately becomes Teddy's godfather, but Teddy was deleted from the movie.
The hint that Neville (Matthew Lewis) ends up in a relationship with Luna Lovegood (Evanna Lynch) was created especially for the movie. J.K. Rowling had revealed that both Neville and Luna married different people long before the final movie came out.
In the first movie, 'Harry Potter and the Sorcerer's Stone', Harry's chocolate frog flies out the window of the Hogwarts Express. What happened to said frog is unknown, but in the epilogue of Harry Potter and the Deathly Hallows Part 2, a chocolate frog is seen climbing up the window of the Weasley and Potter children's carriage.