Oh, my. Guys, apperently we're not done with it. Sorry, but I oppose the idea of giving everybody english based roster. It's just not fun.
Starks: Sicily.
Lannisters: England.
Tyrrels: France.
Dorne: Spain.
Baratheons Renley: Venice.
Baratheons Stannis: Portugal (mixed western - moorish troops may refer to his Free cities mercenaries).
Riverlands: Milan.
Greyjoys: Danemark. At least, we all agree on this.
Arryns: Poland, or HRE.
Mountain Clans: Scottland.
Kings Landing: Rebels. See one of my posts why.