Game of Thrones explores the strengths and weaknesses of a feudal monarchy. Most of Westeros sits in the domain of one of several Great Houses, which claim power by genetic lottery. Fans know the big names, like Houses Stark, Lannister, Baratheon, or Targaryen. Almost every dominant family has several vassal houses pledging fealty. House Karstark is one of House Stark's most loyal retainers, but a series of vengeful decisions led to a tragic downfall.