6. Might Have Beens
Image: Digital Spy
Several well-known actors actually turned down roles in the show, most notably Gillian Anderson. (No one knows which role, but it could have been Cersei.) Dominic West turned down the role of Mance Raydar. Meanwhile, Outlander star Sam Heughan auditioned seven times for various roles, including Renly Baratheon and Loras Tyrell, but was never cast.
