I literally have no clue where you're going with this. One of the most famous medieval noble houses is not a valid inspiration for a D&D noble house? What?
OK, so the idea was, you have two humans: a Renaissance-era, foppish-looking aristocrat and a barbarian chief (son of barbarian chief, grandson of barbarian chief, etc.). Both would be considered nobility from a noble lineage in their own culture. The noble background feature says that a noble can get an audience with another noble. But this is ridiculous, because the two cultures are as as different as possible; there's no way that your noble feature would get you an audience with the nobles of such a vastly different culture, right?
There are a couple of ways of thinking about this.
One is that D&D has typically has a rather narrow idea of what a noble actually is. In art, flavor text, and even statblocks throughout the editions, the concept of nobility has been reserved for a very Medieval-to-Enlightenment-era Europoean style of nobility (lives in something like a palace, has a complex title and coat of arms, has at least a
small army, probably employs a trusted advisor who wears a Van Dyke and is just looking for the opportunity to betray them, etc.).
So no, the noble feature wouldn't work because because D&D never expected that the barbarian chief would be considered to be a noble in the first place.
The disconnect is that we players often
do consider the chief to be a noble, but of a vastly different culture, and so on the face of it, the feature doesn't make sense.
On the flip side, D&D is multiracial, with hundreds of different sentient species and sub-species, of which a sizable fraction have some sort of social hierarchy of a type that would lead to a noble class. In a setting like this, the nobility would almost certainly be taught the
basics of how to deal with nobles of a different culture, if not in an etiquette class then at least by parents and those trusted advisors.
Thus, a noble of one culture
should be willing to meet with a noble of another culture--maybe from a true willingness to meet with other nobles, maybe out of politeness, maybe out of curiosity, maybe because you don't want to start a war just because you refused to meet with the hoboblin warlord who has a hundred thousand troops at his disposal and doesn't like being snubbed. And note the feature says "You can secure an audience with a local noble if you need to," not "you can get the noble to actually listen to you and do what you ask of them."
(Which is another reason I honestly don't really care
that much about pointing to a real-world example of something, because no real-world example is going to involve multiple different intelligent species, magic, active gods, and all the other things that D&D has.)
