So, by the numbers:
you are half of a parent 50%
you are 1/4 of a grandparent 25%
you are 1/8 of a great-grandparent 12.5%
you are 1/16 of a great-great-grandparent 6.25%
and you are 1/32 of a great-great-great-grandparent 3.125%
By 6 generations ago, if no one married a relative, the percent of DNA from a single ancestor is a mere 1.5625% so by 7 generations ago, the percentage is so small as to not make much difference, as the percentage of DNA shared by all humans is 99.9%; chimpanzees share about 98% of a person’s DNA.
So, more than 6 generations would not be significant, even though their DNA can influence a child, such as a child being born with bright red curly hair when all know relatives have black hair, etc.
So, if your great-great-grandmother was Indian, your grandmother would have been 25% Indian, which is less than half, so she should have listed herself as white. The general rule is 50% or so, but obviously varies. E.g., some with a black ancestor might appear white after only 2 generations; some might still appear black after 4 generations.
As is the case in every single one of these stories, you start with your own birth certificate and work backwards one generation at a time using birth/marriage/death certificates. A Census would be useless in determining your ancestry, as either a Census taker listed the race and might call a white man an Indian or a black if the white person had a dark complexion, or call an Indian or a black person white if the skin was paler than others of the same race.
Of course, if you could find her in the Dawes or other Rolls, you would have your proof positive. The best places for searching those would be either the National Archives of the Library of Congress (www.loc.gov/). And, don’t forget the B.I.A. (Bureau of Indian Affairs).
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By 6 generations ago, if no one married a relative, the percent of DNA from a single ancestor is a mere 1.5625%
NIKK..My maiden name is also on my mother’s side of the family.
By all intense purposes, Fauxcahontus STILL isn’t a Native American.
Saying now that she is 1/1000/32nd or some such rubbish.
And according to your post, that would be nothing.
Now you, OTOH, do qualify.
Correction~ Fauxcahontus is 1/1000/24th. LOL
I think she needs to take about 10 years off from politics to research her ancestry. Then she can write a book and try to sell it.