After months of speculation, we finally know who will be playing Randyll Tarly, the legendary father of Samwell Tarly (John Bradley) in Season 6 of Game of Thrones. Watchers on the Wall reports that Downton Abbey star James Faulkner has signed on to play Randyll Tarly, with Samantha Spiro and Rebecca Benson coming aboard to play Sam's mother and sister, respectively. They join the previously-cast Freddie Stroma, who is playing Samwell's younger brother Dickon Tarly.

All of these actors will reportedly be filming in Spain this week, although no details were given for the scenes they will shoot. When we last saw Sam, he left the Night's Watch with Gilly (Hannah Lawrence) and her young son, on his quest to become a maester. It has been rumored that, along the way, Sam will visit his home, House Tarly of Horn Hill, which is where we'll likely see Sam's father, mother, sister and brother. Of course, it isn't known at this time how many episodes each of these actors have signed on for in Game of Thrones Season 6, but it certainly could be a tense reunion for all involved.

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Sam was essentially forced to join the Night's Watch by his father, who believed that his oldest son was a disappointment, and not a worthy heir to House Tarly. With Sam at the Wall, his younger brother Dickon would take over and rule House Tarly when Randyll passed on. Sam has occasionally mentioned his family throughout the first five seasons of Game of Thrones, but this is the first time that we'll actually meet them. It's worth noting that, in the books, Randyll forbade Sam from going to Oldtown to become a maester, when he was younger. Now that Sam is actually becoming a maester, we'll have to see how his father reacts to this news.

James Faulkner, Samantha Spiro and Rebecca Benson join new Season 6 cast members Ian McShane in an unspecified role, Pilou Asbæk, who has been rumored to be playing Euron Greyjoy, the uncle of Alfie Allen's Theon Greyjoy and Max von Sydow as the Three-Eyed Raven. Richard E. Grant and Essie Davis are the most recent casting additions, portraying members of a theater troupe who are putting on a play about famous figures in Westeros. There are still a number of new characters that have yet to be cast, so stay tuned for more casting updates.

James Faulkner is best known for playing Lord Sinderby in PBS' Downton Abbey, and Pope Sixtus IV in Starz's Da Vinci's Demons. Samantha Spiro stars in the U.K. miniseries London Spy, while Rebecca Benson will next be seen in Macbeth, alongside Michael Fassbender. What do you think of these new cast members? Chime in with your thoughts and stay tuned for more casting updates.