The best source of information are the works of N. Brent Kennedy, formerly of Wise Virginia where he was at the Clinch Valley Community College. He is now down south 60 miles in Kingsport, Tennessee.
He learned of his Melungeon heritage in an Atlanta GA hospital where he was diagnosed with a rare genetic disorder generally restricted to eastern Mediterranian people. The near brush with death set him to wondering...."who the hell am I?"
His works are fascinating to those of us who live here and have contact with the various Melungeon families in the area. They too are fascinated and are "Coming Out" There is now an annual gathering in Kingsport drawing hundreds who are interested in their heritage and genetic problems.
Although there are pockets of Melungeon folks in all the mountains of North Carolina, Virginia, West Virginia and Tennessee, the primary redoubts were in the counties on the Clinch River in Tennessee.....Hancock and Claiborne. Across the river is Southwest Virginia and there are Melungeon families all up through there as well. The racially indeterminate people were severely persecuted and fled to the mountains and hollows where no one would bother them.
The gathering focuses attention on the heritage and the main certainty now is that the issue is quite complex. Melungeons are a mix of White, Negro and Indian blood. The white componant is genetically similar to some Portugeese people thought to be descended from North African Moorish people who settled there from Turkey.
There are academics in the past who have written extensively and now appear to be off base and naturlly want to defend themselves even if wrong. The current effort is quite extensive, both private and I think academic, and will result in a clearer and more accurate picture than is now available.
The family histories are being studied and once taboo secrets are being discussed in the light of day. One certainty is that these people have been here from the very beginning ie 1580's or so and are among the very earliest Americans. Some place them at Santa Elena (Beaufort SC) as early as 1566. The Lost Colony of Dare County NC is also widely thought to have produced Melungeon famalies.