Jack Gleeson (Joffrey) received a letter from author George R.R. Martin after the show aired, stating "Congratulations on your marvelous performance, everyone hates you!"
There is not a single character that appears in every episode, and only three characters have appeared in every episode of a given season: Lena Headey (Cersei Lannister) and Jack Gleeson (Joffrey Baratheon) appeared in every episode of the first season, and Peter Dinklage (Tyrion Lannister) appeared in every episode of the second and fifth seasons.
Emilia Clarke (Daenerys Targaryen) was doused in so much fake blood during one scene that she got stuck to a toilet seat during a break.
In the year 2012, over 160 baby girls in the U.S. were legally named "Khaleesi", after the character in the show, although it is not the character's name (Daenerys) but rather a title.
Charles Dance dressed an actual stag carcass on-camera for Tywin Lannister's first scene. Dance was shown the procedure the previous day by a butcher.
In the unaired pilot, George R.R. Martin cameoed as a Pentoshi nobleman at the wedding of Khal Drogo and Daenerys Targaryen. The scene, alongside most of the pilot, was subsequently reshot and Martin did not appear.
The first season used Northern Inuit dogs, a type specifically bred for wolf-like appearance, to stand in for the direwolves (the Stark's house sigil). However, since direwolves are known to be much larger than normal wolves, real wolves were digitally composited into scenes for season 2. This strained the budget and the schedule, hence why there are only a handful of scenes with Grey Wind (Robb Stark's wolf), Summer (Bran Stark's wolf) and Shaggydog (Rickon Stark's wolf); Ghost, who belongs to Jon Snow, is shown in brief glimpses.
As of 2014, it is the most watched HBO TV-Series of all time, with an average viewership of 16.1 million (Season 4), slightly ahead of a record which was previously held by The Sopranos (1999-2007).
Theon Greyjoy is played by Alfie Allen, brother of singer Lily Allen and was the inspiration for her song 'Alfie'.
Each season shoots annually from July to December. Two units, the 'Wolf' and the 'Dragon', shoot concurrently in various countries.
The showrunners David Benioff and D.B. Weiss said the production of the show is a massive undertaking. The production lasts the entire year and they shoot the show like a 10-hour movie. Season 5 alone was shot in 5 countries, on 151 sets, for 240 days, having 166 cast members, over 1,000 crew members and over 5,000 extras.
Both Jack Gleeson (Joffrey) and Aidan Gillen (Littlefinger) appeared in Christopher Nolan's Dark Knight Trilogy. Gleeson appeared in Batman Begins (2005) while Gillen appeared in The Dark Knight Rises (2012). Richard Brake, who portrays The Night's King, also appeared in Batman Begins as Joe Chill, whereas Burn Gorman (Karl Tanner) appeared in The Dark Knight Rises.
After filming his death scene, Sean Bean played football with his replica head.
In every season, at least one king (or claimant) dies. In season one they are Robert Baratheon (King on the Iron Throne), Viserys Targaryen (claimant to the Iron Throne), and Khal Drogo (a Khal is a chieftain similar in position to a king); in season two Renly Baratheon (claimant to the Iron Throne) and Xaro Xhoan Daxos (King of Qarth); in season three Robb Stark (King in the North); in season four Joffrey Baratheon (King on the Iron Throne); and in season five Mance Rayder (King Beyond the Wall) and Stannis Baratheon (claimant to the Iron Throne).
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