Just to clarify for others reading this... There is *NO* proof that the Gurganus family is in any way connected with the Madoc expedition 600+ years earlier, or that it has Welsh origins, or that the family interacted with the Raleigh expedition, or that they were considered Indians. This is all pure speculation. To make these claims as fact, they need to be backed up with proof.
John Masterson Gurganus was born in the early 1800's, and we have known Gurganus's going back to the early 1700's. So he did most likely have "Gurganus" ancestors. That we don't know his parents is more likely due to courthouse fires destroying original documents.