Carla:
As you may be aware, the Harris line is one of the few families that has been well documented as having Native American blood; specifically, Cheraw or Choctaw.
My maternal Grandfather's mother was Fannie Harris-Royal. As was handed down to us, the Harris appeared white (appeared of Spanish or French descent), and were accepted as such.
However, according to my mother, she was told their was some "mixture" many, many generations before Fannie Harris-Royal.
I have traced this Harris line to Brunswick County, VA - headed by Tom and Fannie Harris (W) during the early 1800's. Therefore, any non-European lines would most likely have been present at the latest during the mid-1700's.