When Game of Thrones casting calls began, nearly every British actor auditioned - both aspiring and the already established. Even though nobody could dream of the levels of success the show and the cast members enjoyed in the years that followed, it was clear that it was an opportunity that shouldn't be missed.

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In the years that followed, the show kept introducing new characters. Many celebrity fans of the show wanted desperately to land a role in the iconic HBO series. While some actors turned down the role themselves and never looked back, others suffered rejection. Also, many found success in other projects in the years that followed.

10 Sam Claflin

Sam Claflin wasn't rejected for the roles on Game of Thrones - he changed his mind himself. According to Cinema Blend, he was auditioning for either Snow White and the Huntsman or Pirates of the Caribbean at the same time.

If he stayed in the running, he might have gotten the part of Jon Snow or Viserys Targaryen as he auditioned for both. While Claflin is a huge fan of the series, he doesn't regret changing his mind. After all, he already starred in another massive project, The Hunger Games.

9 Jennifer Ehle

PARK CITY, UT - JANUARY 22: Actor Jennifer Ehle attends the 'The Miseducation Of Cameron Post' And 'I Like Girls' Premieres during the 2018 Sundance Film Festival at Eccles Center Theatre on January 22, 2018 in Park City, Utah. (Photo by C Flanigan/FilmMagic)
via getty images

Jennifer Ehle is most famous for her role of Elizabeth Bennet on the 1995 BBC adaptation of Pride and Prejudice. She was already cast as Catelyn Stark and performed in the original pilot episode of Game of Thrones, but she later on changed her mind.

At the time of shooting season 1, Jennifer Ehle just became a mother. Rather than bringing up fictional Stark children, she chose to dedicate her time to her daughter Talulah. She watched the series as it came out and she thinks that they made the right casting choices.

8 Gillian Anderson

According to Daily Mail, Gillian Anderson turned down the offer to portray an important character on Game of Thrones because it was too big of a time investment. " If I am going to be spending that amount of time working on something, I would rather be working with a director like Martin Scorsese," she said.

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Her daughter despaired when the X Files star turned down the opportunity. It's speculated she was in the running for Cersei Lannister. Luckily, she had a lot other projects in the following years. From Sex Education to The Crown, Anderson's acting range is unbelievable.

7 Perdita Weeks

While established actors, such as Anderson and Claflin, don't regret turning down the opportunity to be cast on Game of Thrones, those less famous just might. After all, Game of Thrones was undoubtedly a life-changing experiences for a number of actors who might never be famous otherwise.

Perdita Weeks is most famous for her portrayal of Mary Boleyn on Showtime’s The Tudors. Her experience with period dramas definitely worked in her favor when she auditioned for the role of Roslin Frey. Unfortunately, she had to turn down the role because she had to go shoot The Heretics. What's worse, the shooting was then postponed and she asked for her Game of Thrones role back, but it was too late as the part already went to Alexandra Dowling.

6 Mahershala Ali

Mahershala Ali prepared really well prior to auditioning for Xhoan Daxos, but the audition didn't go as he planned. When on Jimmy Kimmel, Ali shared that the casting director called him to stiff.

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But even though he wasn't cast on that fateful day, this outstanding actor enjoyed a lot of success in the following years. He got two Academy Awards for Best Supporting Actor and he starred in the third season of True Detective.

5 Sam Heughan

Sam Heughan was a big fan of The Song of Ice and Fire long before HBO decided to do a screen adaptation. According to Vulture, he auditioned seven times, but to no avail. He was willing to portray anybody: from Renly to a member of the Night's Watch.

Since 2014, Heughan has been starring in Outlander, so everything turned out just fine in the long run for him!

4 Izzy Meikle-Small

When choosing the girl to play Sansa Stark, it came down to two actors: Sophie Turner and Izzy Meikle-Small. While Turner landed the role that ultimately put her on a completely different life path, Meikle-Small was a little bit disappointed. She told The Telegraph that she is at peace with the casting director's decision and that she thinks that her parents wouldn't be happy about all the nudity featured on the show.

The 25 year-old landed roles in other movies, but she's not as famous as other Game of Thrones stars - at least not yet.

3 Jared Harris

The Mad Men star Jared Harris was a huge fan of the show and he wanted desperately to be cast as the High Sparrow. Unfortunately, he was deemed too young to play the role. The sect leader was one of the most important characters in seasons 5 and 6. Harris has instead starred in HBO's Chernobyl and The Crown.

2 Tamzin Merchant

If it wasn't for Tamzin Merchant turning down the role of Danaerys Targaryen after already appearing in the original pilot episode, Emilia Clarke might have never been a household name.

The Carnival Row star has since opened up about her decision to leave Game of Thrones. She told EW that "it was a lesson that if my guts are telling me a story isn't something I'm excited to tell, then I shouldn't try to be excited just because other people are telling me that I should be excited." The pilot episode was definitely not easy to shoot for neither of the Danaerys actresses. "I found myself naked and afraid in Morocco and riding a horse that was clearly much more excited to be there than I was," recalled Merchant.

1 Millie Bobby Brown

Millie Bobby Brown is one those actors who nearly gave up trying to make it in the world of show business. Right before landing Stranger Things, she auditioned for Lyanna Mormont, but was rejected.

Rejection is never easy, but it's even harder when it's for a role actors feel really passionate about. Millie Bobby Brown didn't get to act in Game of Thrones, but she's doing just fine nonetheless.

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