Robin Williams was turned down from playing Hagrid in Harry Potter due to J.K. Rowling rule

The late Robin Williams was willing to be part of the Harry Potter franchise, but J.K. Rowling had a strict rule that prohibited him from being cast in the iconic movies.

From Flubber and Mrs. Doubtfire, to Hook and Jumanji, Williams was a household name in many family favourite films.

But another accolade the late Hollywood legend wanted under his belt was a role in Harry Potter, with Williams having eyed up the part of Rubeus Hagrid - the beloved Keeper of Keys and Grounds of Hogwarts.

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Williams was so keen for a part in the films that he contacted Chris Columbus, the director of the first two Harry Potter movies, directly in the hopes of being considered.

Columbus had to turn down Williams, however, due to a strict rule J.K. Rowling had enforced when it came to the cast of the films.

Instead, Robbie Coltrane got the part of Hagrid, and went on to receive worldwide recognition for the role.

Explaining why Columbus had to say no to Williams, Janet Hirshenson, the casting director for the Harry Potter films, told the Huffington Post back in 2016: "Robin [Williams] had called [Chris Columbus] because he really wanted to be in the movie, but it was a British-only edict, and once he said no to Robin, he wasn’t going to say yes to anybody else, that’s for sure."

Warner Bros.

Williams didn't just shoot his shot for Hagrid either, he also expressed interest in the role of Remus Lupin who made his first appearance in the third film of the franchise, Harry Potter and the Prisoner of Azkaban.

Again, Columbus had to say no to the Good Will Hunting star - something he admitted was 'difficult'.

In 2021, he told Total Film: "I had a conversation with Robin Williams, who wanted to play Lupin. It was very difficult for me to say ‘It’s all British. There’s nothing I can do.'"

While Columbus praised David Thewlis, who went on to get the part, he also noted that Williams would have been 'brilliant'.

"Robin would have been brilliant. It would have been a different interpretation - I thought David Thewlis was great - but Robin would have been brilliant," the director told Insider.

But Columbus kept his promise to Rowling and the Harry Potter cast remained fully British.

Verne Troyer was the only American actor cast throughout the franchise. He portrayed - but did not voice - Griphook in Harry Potter and the Philosopher's Stone. The character was voiced by Warwick Davis.

Davis later replaced Troyer as Griphook in Harry Potter and the Deathly Hallows: Part 1 and Harry Potter and the Deathly Hallows: Part 2.