Honestly, I don’t think the issue of “who is Indigenous” can be conflated with “how long until you’re not mixed” because of blood quantum requirements. Cherokee Nation citizenship, for example, doesn’t have BQ requirements. You have to have at least one direct provable ancestor on the Dawes Rolls (which in and of itself may pose a problem because your direct Ancestor may have not met BQ requirement when the rolls were made and it wasn’t uncommon for the government to disenroll NDNs from various Nations who went to higher education schools, moved off allotted tribal lands, or married a non-NDN)
Even different bands of the same Nation have different requirement–using the aforementioned example, Eastern Band Cherokee citizenship requires you to be 1/16th or more. Ute require 5/8 or more (they were recently talking about lowering it but I haven’t kept on if they did); is someone not Ute anymore if they’re “only” ½ and can’t enroll? My Nation–the Blackfeet, part of the greater Blackfoot Confederacy–require a fourth or more but I have no idea what the requirements are for the other three bands as they’re in Canada and that’s a whole other thing going on with Status and enrollment
There are people on the Blackfeet reservation who are as Niitsitapi as anyone and culturally connected but are ineligible for enrollment since the change from the direct descendancy rules to the quarter+ requirement in the early 60s
Your enrollment determines whether or not you can vote in tribal elections, certain services you can use, and other things available to only enrolled members of a given Nation; it doesn’t determine whether or not you’re NDN. The issue of who’s NDN and blood quantum laws is honestly a discussion for a whole different blog. Like I’ve said a few other times addressing this; anyone can say they’re NDN but there’s a difference between being Native and having Native heritage. People in the US are really fond of blood myths when it comes to NDNs. Everyone’s great-grandmother was a “Cherokee Princess” or whatever. The Cherokee Nation itself isn’t seen as “fake” in NDN country, just that there’s a lot of fakes who claim to be Cherokee; that’s not the same thing
Honestly, when it comes to Indigenous North American Nations–if someone claims to be from a particular Nation, there should be more information then the stock “my [distant relative] had [high cheekbones/tan skin/dark hair/looked NDN from this picture I saw/insert your favourite stereotype].” And I understand that people are or get disconnected, unfortunately, that happens…but being honest and upfront about what you do and don’t know is what’s important. Some rando talking about distant heritage and suddenly everyone’s a princess or a pipe carrier or they’ve watched Smoke Signals three times and now they’re from the rez; that’s suspect
But because of the issue with blood quantum and a myriad of issues present in NDN Country because of the nature of closed cultures, the after effects of genocide, the continuing cultural and paper genocide, and certain pervasive attitudes; you really can’t make a clear delineation on “this is the point at which someone isn’t NDN”
As far as any other kind of mix goes; I don’t know that anyone can really answer that. Where do you stop drawing lines? Where do you start drawing lines?
I think it’s a matter of how you normally identify. Is someone overwhelmingly [race(s)] and only ever identifies as [other race(s)] when it’s convenient to the conversation or in order to speak over someone else? I would say they’re definitely not mixed with whatever is being filled into that second bracket; but that’s me