OK.
Zuerst wird einmal das Haus, aus dessen Umfeld wir enstammen, sozusagen ausgewürfelt.
Du hast recht, wir werden nicht einem der grossen und bekannten Häusern angehören, sondern einem Vasallen derer.
Dies geschieht, indem wir jeweils insgesammt 7d6 in den folgenden Kategorien werfen (ich zitiere einfach mal aus dem PDF):
Defense
Defense describes fortifications, castles, keeps, towers, and other structures that serve to protect your holdings. Defense also describes the presence and quality of roads, representing the ability to move troops and supplies to threatened areas.
Influence
Influence describes your presence in the Seven Kingdoms, how other houses see you, and the notoriety attached to your name. A high Influence resource typically describes one of the great houses or the royal family, while a low Influence resource would describe a house of little consequence, small and largely unknown beyond the lands of their liege.
Lands
Land resources describe the size of your House’s holdings and the extent of their influence over their region. A high score describes a house that controls an enormous stretch of terrain, such as Eddard Stark and the North, while a small score might represent control over a small town.
Law
Law encompasses two things: the extent to which the smallfolk respect and fear you and the threat of bandits, brigands, raiders, and other external and internal threats. Law is something your family must maintain, and if you don’t invest in keeping your realm safe, it could fall into chaos.
Population
Population addresses the sheer number of people living in the lands you control. The more people there are, the more mouths you have to feed. However, the more people there are, the more your lands produce. This abstract value describes the quantity of folks that live under your rule.
Power
Power describes your house’s military strength, the ability to muster troops and rouse banners sworn to you. Houses with low scores have few soldiers and no banners, while those with high scores may have a dozen or more banners and can rouse an entire region.
Wealth
Wealth covers everything from coin to cattle and everything in between. It represents your involvement and success in trade, your ability to fund improvements in your domain, hire mercenaries, and more.
Diese Werte werden nun je nach Region modifiziert (hat Pendragon schon erledigt) und zum Schluss des ersten Schrittes kann nun jeder Spieler nocheinmal 1d6 zu einer Kategorie seiner Wahl addieren.
Im zweiten Schritt werden nun historische Ereignisse, die über das Haus hereinfallen abgehandelt. Auch sie modifizieren die oben genannten Werte.
Das alles hat, wie du richtig schreibst, erstmal nur bedingt etwas mit den Charakteren zu tun. Es gibt lediglich einen Anhaltspunk auf das Umfeld.
Deinen Char erstellst du erst im Nachhinnein.