I knew my great-grandmother, Adeline Marchand, born Tessier, was Indian, but I have discovered, through genealogical research, that she had roots in Akwesasne, so she was Mohawk through her mother, Catherine Robidoux, daughter of Joseph Etienne Robidoux and Marguerite Gendron.
Further research - on how the Robidoux, descendants of a Spanish sailor, could have become Mohawks - revealed the existence of the "White Indians", white settlers who integrated indigenous communities.