The idea that there was a uniform code to which all nobility adhered is ridiculous. It's even more ridiculous when you consider how loosely other aspects of the game are expected to mirror history. So, riding around the kingdom, fighting undead in the name of the Supreme Chancellor is historically accurate, but a noble who sells his military service in exchange for wealth isn't. Never mind the fact that that's literally what nobles did, it is still historically false, based on some vague, perhaps even non-existent, interpretation of Europe circa 700-1300AD.
