• Arryn of the Eyrie
  • Baratheon of the Storm's End
  • Greyjoy of Pyke
  • Martell of Sunspear
  • Stark of Winterfell
  • Targaryen of King's Landing
  • Tyrell of Highgarden

To see the available houses you can take, refer to this page.
You can become a member of a house with said house's leader's permission.