While they don't play too large a role in the first season of Game of Thrones, one of my personal favorite houses is Greyjoy. House Greyjoy is basically a Viking analog, as it is comprised of seafaring raiders who make their home on the cold, brutal Iron Islands. Prior to the start of Game of Thrones, the leader of the Greyjoys, Balon, rebelled against the Baratheon throne, but his revolt was put down by Eddard Stark. As a result, the Starks took Balon's son Theon as a ward and hostage, to ensure Balon's good behavior moving forward. Theon is a wry, cynical, amoral youth, but a staunch supporter of his foster brother Robb.