HBO have issued a comprehensive cast list for Game of Thrones, including many roles previously unannounced. The bigger names I will save for another post. This is going to be a long one.
Francis Magee may not be a household name, but pretty much anyone who's watched any British drama in the last decade will recognise him from a plethora of roles he's played on TV and in film, with roles ranging from stints on EastEnders to the Daniel Craig movie Layer Cake. He recently appeared in the one-off docu-drama Trafalgar Battle Surgeon, had a guest stint in Survivors and a recurring role on City of Vice. Magee is playing Yoren, a member of the Night's Watch who acts as a recruiter, visiting cities and castles and offering to take their convicts off their hands to join the Watch. This is a relatively small casting decision in the grand scheme of things, but a finely-judged one.
Peter Vaughan is a veteran British actor with a very long and distinguished career, with credits stretching back to the 1950s. Among his more notable roles is Admiral Hood on the Hornblower TV movies, but his other credits include The Saint, Citizen Smith, Heartbeat, Our Friends in the North, The Avengers, Boon, Lovejoy, The Sweeney, Porridge and even Morecambe and Wise. He is playing Maester Aemon, the oldest man in Westeros, the maester at Castle Black and one of the closest advisors to Lord Commander Mormont.
Margaret John is another British actress of long standing, with roles in many notable productions since the 1960s. She is one of a few actors to have appeared in both incarnations of Doctor Who, appearing as Grandma Connolly in The Idiot's Lantern under the new regime and as Megan Jone in the 1968 serial Fury from the Deep. She also played the small but crucial role of the Arbiter in the first episode of Blake's Seven, sentencing Blake to the penal colony of Cygnus Alpha and kick-starting the entire series. Her more recent credits include Being Human and Gavin and Stacey. She is playing 'Old Nan', the oldest resident of Winterfell, a former loyal servant who is now effectively retired, but still tells the Stark children stories. She is engaged in a minor battle of wills with Maester Luwin (Donald Sumpter), who is left to rationalise or explain in scientific terms the legends she tells the children. Old Nan is also the grandmother or great-grandmother of Hodor (Kristian Nairn).
Continuing the line of excellent, long-established British actors appearing in the series is Sir John Standing (technically Baron John Standing, but he doesn't use the title), an actor with a lengthy pedigree stretching back to the 1960s. His most recent genre role was in the film V For Vendetta, but he has a prior GRRM connection, having appeared in the 1980s movie based on his short story Nightflyers. On Thrones he is playing Lord Jon Arryn, a character whose demise sparks the events of the series. He appears in flashback.
Gethin Anthony is playing Renly Baratheon. Anthony is another young actor with some theatre work who has done the rounds of several British soaps. His character of Renly is King Robert Baratheon's youngest brother. Whilst King Robert has gone to seed somewhat, Renly remains in the prime of life, a charismatic and popular warrior and a member of the King's small council, where he serves as Master of Laws.
Kate Dickie is playing Lysa Arryn. After a number of roles on TV and film (starting, amusingly, in Scottish sitcom Rab C. Nesbitt many years ago) she will imminently be appearing as Agnes in the Starz mini-series Pillars of the Earth, based on the Ken Follett novel. She has also won a Scottish BAFTA for her leading role in the film Red Road. In Thrones she is playing the sister of Catelyn Stark (Michelle Fairley). Lysa is the widow of Lord Jon Arryn and the mother of his heir, Robin (not a typo). She used to have a major crush on Littlefinger (Aidan Gillen). Lysa appears relatively briefly in the books but her actions and words have huge and lasting consequences in the story.
Lino Facioli is playing 'Robin' Arryn. Facioli is a very young actor but who has already picked up some notable roles, most recently appearing in the film Get Him to the Greek. His Thrones character is known in the books as 'Robert Arryn', but between King Robert and Robb Stark, it was decided to modify his name for the series to keep things less confusing. His new name allows him to keep his nickname from the books of 'Sweetrobin', however. Robin is the very young and sickly son of Lord Jon Arryn, and becomes Lord of the Vale upon his father's death. He has led a sheltered life, coddled by his mother, and is not a strong child.
Eugene Simon is playing Lancel Lannister. Simon's most notable previous roles were in the Russell T. Davies drama Casanova, where he played the younger version of David Tennant's title character, and in the Ben-Hur mini-series, playing the younger version of the title character. In Thrones he plays the cousin of Cersei, Tyrion and Jaime Lannister, one of King Robert Baratheon's squires.
Derek Halligan is a Northern Irish actor who started out as a singer in a band in the 1970s before moving into theatre with a stint in Jesus Christ, Superstar. Most of his career has been spent on the stage, but he recently appeared in British soap Hollyoaks and as supervillain Dr. Nightshade in the 2000 movie Tonight We Fly. In Thrones he plays Ser Alliser Thorne, the trainer of the new recruits to the Night's Watch and not a friend of Jon Snow and Samwell Tarly. He is known for the condescending nicknames he gives to the new recruits (such as 'Lord Snow' and 'Ser Pigg' for Jon and Sam).
Dominic Carter is a British actor with a recurring role on Coronation Street as policeman DC Hooch (oddly appropriate). He had a recurring role on modelling drama Drop Dead Gorgeous and many other TV credits, including My Family and Black Books. In Thrones he is playing the role of Janos Slynt, the commander of the King's Landing City Watch, the goldcloaks (effectively the city's chief of police).
Susan Brown is playing Septa Mordane. Brown is a familiar face to British audiences, appearing in many TV roles over the years. Her most recent notable appearance was as Bridget Spears in Torchwood: Children of Earth. Her character of Septa Mordane is a septa (priestess) in the service of House Stark, responsible for the education and comportment of Lord Eddard's two daughters.
Josef Altin is playing Pyp. Altin is a young British actor with extensive television credits, including recent appears in 'superhero' drama Misfits and in the popular UK genre series Being Human. Pyp is another recruit of the Night's Watch, and is one of Jon Snow and Samwell Tarly's friends at the Wall.
Dermot Keaney is playing the recast role of Gared, replacing Richard Ridings from the pilot. Keaney has a number of TV and film appearances, but his highest-profile role was as Maccus, Bill Nighy's second-in-command in the second and third Pirates of the Carribean film. You won't recognise him, though, as he was buried behind a ton of CGI and prosthetics. He was the guy with the hammerhead shark head. Gared is one of the three rangers of the Night's Watch who get into trouble in the prologue.
Brendan McCormack is playing Ser Vardis Egen. McCormack has a recent role in The Tudors and a number of roles in theatrical productions. Ser Vardis Egen is the captain of Lord Jon Arryn's household guard and is a loyal servant of House Arryn at the Eyrie.
Emun Elliott is playing Marillion. Elliott recently appeared, appropriately, in the movie Black Death with Sean Bean, as well as SF-tinged television drama Paradox. Marillion is a singer and minstrel, chance-met on the road by Catelyn Stark, who attaches himself to her party. Martin was surprised not to be asked to change his name, due to the number of fans who've linked the character to the band when GRRM had never heard of them previously.
Jefferson Hall is playing Ser Hugh of the Vale. Hall is another young British actor. His most notable recent appearance was in the latest BBC adaptation of Emma. Ser Hugh, for those who may not remember the character, was Lord Jon Arryn's squire whom King Robert knighted upon his lord's death for his leal service.
Ciaran Birmingham is playing Mord, a jailor at the Eyrie. Birmingham is another experienced stage work who has played some minor roles on TV, most recently a brief appearance in The Tudors.
Antonia Christophers is playing the role of Mhaegen. Christophers is a stage actress with no major screen credits to date. Mhaegen isn't a new character, but is 'Barra's mother' in the book. She was given a name for the TV series (something Martin also did for Ros, as he felt that 'Red-Headed Whore' wasn't good enough).
Rhodri Hosking plays the role of Mycah. Hawkings appears to be a newcomer to the acting world, with Mycah his first role of note. Mycah is the son of a butcher who falls in with King Robert's party as it returns to King's Landing, and befriends Arya Stark.