J.K. Rowling's Harry Potter series led to the creation of one of the biggest book fandoms to date. The fandom grew even larger once the film adaptations hit the big screen. The eight films based on the books required many actors for both significant roles and background extras. The recruitment of extras allowed fans to appear alongside legendary actors and even included future Bridgerton star, Regé-Jean Page.

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The casting of certain characters was carefully done to do justice to the character's original version in the books. While the casting decision of The Golden Trio of Harry, Ron, and Hermione was among the easiest, several actors weren't the initial choices for some characters. Notable stars have turned down major roles in the franchise, which could have been different if they had accepted the parts.

11 Ian McKellen Couldn't Replace An Actor Who Didn't Approve Of Him

Sir Ian McKellen as Magneto using his powers

One of the most well-known potential castings was Ian McKellen as Dumbledore. Richard Harris played the Hogwarts headmaster in the first two films but had passed away before Harry Potter and the Prisoner of Azkaban. Due to his death, McKellen was approached as Harris' possible replacement.

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McKellen had previously played Gandalf, another famous wizard in the Lord of the Rings franchise, so his potential involvement seemed obvious. However, he turned down the role because he couldn't replace an actor who didn't approve of him. Therefore, the role was given to Michael Gambon.

10 Robin Williams Was Rejected For Two Roles

Robin Williams in Flubber looking shocked.

The late Robin Williams was a comedic legend best known for his voice-acting role as the Genie in Disney's Aladdin and various 1980s and 1990s films, like Jumanji. Years after the release of Harry Potter and the Deathly Hallows - Part 2 and Williams' death, casting director Janet Hirshenson revealed he really wanted to be in the film as either Hagrid or Lupin. However, Williams was rejected due to the British-only rule for the films. Therefore, the part went to Rowling's first choice, Robbie Coltrane, instead.

9 Hugh Grant Had Prior Film Commitments And Turned Down The Gilderoy Lockhart Role

hugh grant nicole kidman

Hugh Grant first gained attention for his role in the 1994 film Four Weddings and a Funeral. Although, he became even more well-known for his appearances in both Bridget Jones's Diary and Love Actually. Grant was only one of the contenders for the role of Gilderoy Lockhart, who first appeared in the second film Harry Potter and the Chamber of Secrets. He turned down the role due to scheduling conflicts with the rom-com Two Weeks Notice alongside Sandra Bullock, and Kenneth Branagh snagged the iconic role instead.

8 Eddie Redmayne Could Have Joined Franchise Much Earlier

7 Eddie Redmayne in Fantastic Beasts

Eddie Redmayne almost had an earlier role in the Harry Potter franchise, before his lead role as Newt Scamander in the Fantastic Beasts film series. The future Les Misérables star auditioned for the role of Tom Riddle, but it apparently went horribly. Riddle was a Slytherin half-blood wizard who later transformed into the sinister Lord Voldemort.  According to an interview with Empire, Redmayne failed to get a callback, and Christopher Coulson joined the production, although, he was too old to return for Harry Potter and the Half-Blood Prince. 

6 Rowan Atkinson Was Too Comedic To Play Voldemort

Rowan Atkinson

Rowan Atkinson is best known for playing the titular role in the 1990s British sitcom Mr. Bean. He also provided the voice for Zazu in Disney's The Lion King and played the titular role in the spy-comedy Johnny English film series, which was a parody of James Bond.

RELATED: Harry Potter: 10 Times Voldemort Was His Own Worst Enemy

Surprisingly, the comedic actor was among the front-runners for the role of Voldemort. It was even rumored that he had received the role. Fortunately, Ralph Fiennes was cast as He-Who-Must-Not-Be-Named and gave a stellar performance. Harry Potter fans can't imagine Atkinson in an evil role like that anyways.

5 Saoirse Ronan Was Too Young To Play Luna Lovegood

Saoirse Ronan in Little Women as Jo March

Saoirse Ronan gained recognition as a child actress for her Oscar-nominated role in the 2007 film Atonement at just 13-years-old. The future Little Women star was a huge Harry Potter fan at the time of her audition for Luna Lovegood. Ronan lost the part to another Irish actress, Evanna Lynch, three years her senior. Ronan admitted to a gossip blog in 2011 that while she was disappointed about her rejection, she was too young for the role. Luckily, she found fame in other productions.

4 Kate Winslet Was Too Big Of A Name For Helena Ravenclaw

Kate Winslet dines on the Titanic

Kate Winslet rose to global prominence for her lead role in James Cameron's 1997 film Titanic alongside Leonardo DiCaprio. Winslet and DiCaprio developed a close friendship after the film and later co-starred again in the 2008 film Revolutionary Road. The actress also won Best Actress that year for The Reader. Winslet was one of the prospective actresses for Helena Ravenclaw, Rowena Ravenclaw's daughter, but her agent allegedly thought the part was too small for her, and the role went to Kelly Macdonald in Deathly Hallows - Part 2.

3 Tilda Swinton Doesn't Enjoy Films Like Harry Potter

Keanu Reeves and Tilda Swinton in Constantine

One of Tilda Swinton's most recognized roles occurred in The Chronicles of Narnia series as the White Witch. She also joined the Marvel Cinematic Universe as the Ancient One, starting with the 2016 film Doctor Strange. Swinton was one of the contenders for Professor Trelawney, the kooky Professor of Divination. She stated in an interview with Scots Magainze that she disliked films like Harry Potter, and this could be why she turned the role down. Emma Thompson took on the role instead, but Swinton would have done a great job.

2 Rosamund Pike Was The First Choice For Rita Skeeter

Rosamund Pike

Rosamund Pike became well-known for her appearance as Bond girl Miranda Frost in the 2002 film Die Another Day. Another one of her acclaimed performances occurred in the 2014 psychological thriller Gone Girl, which earned her the Oscar nomination for Best Actress.

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The future Wheel of Time star turned down Rita Skeeter for undetermined reasons after she was the first choice for the role. Miranda Richardson consequently snagged the role as the nosy journalist for the Daily Prophet and did the character justice.

1 It Was Rumored Naomi Watts Was Cast As Narcissa Malfoy

naomi-watts-game-of-thrones-prequel-header

Naomi Watts gained recognition for her Oscar-nominated lead role in the 2002 horror film The Ring, which led to her casting in many more productions. Watts also gave an excellent performance as Rose Mary Walls in the film adaptation of The Glass Castle. It was even rumored Watts was recruited to play Narcissa Malfoy in Harry Potter and the Half-Blood Prince, but the rumors were shot down. The late Helen McCrory joined the Harry Potter franchise as Draco's mother and reprised her role in the remaining three films.

NEXT: 5 Perks of Being Draco Malfoy (& 5 Harsh Realities)