I believe that after R.C. discovered this, he held himself in contempt for the rest of his life because he was ashamed of his heritage.
The term Melungeon is first introduced in the novel when Nonnie's father, Claude, discovers that Nonnie's boyfriend (R.C.'s father) is one. He says, "Nigger's won't claim a Melungeon Injuns won't claim them either" (57). This statement proves that the society in which they live, as far as Claude sees it has already created a circle or norm and that black people, Indians and especially Melungeons are on the outside of that circle. This statement sets up a very obvious distinction, and it is a distinction that R.C. is going to notice and pay attention to.
When R.C. finds out that he is the son of a Melungeon man, he recognizes the stigma attached to that claim, because he sets out to prove the fact to be untrue. When he learns that that truly is his heritage, he becomes out of control. He writes, "Best I can recall, my thinking run kindly along these lines, "Mamma is a whore, and I am a bastard" and so by God I set out to prove it." (87). He turned to drinking, fighting and having sex in order to not have to deal with this shocking secret that he had learned. He eventually recovered from this spell, married a girl, had some babies, but I don't think that he ever fully recovered, because he carried the truth of his heritage through the tune he wrote called "Melungeon Man".
R.C. wrote "Melungeon Man" to go along with the other songs that his families performed for a living. His sister Lizzie said of the song, " his own "Melungeon Man", its title referring to a mysterious strain of folks scattered through the mountains" (104). She also said, "Regardless of the origins of the Melungeons, that ballad captures such a feeling of otherness, of being outside, cut off from the rest of humanity, that I never heard them sing it without feeling a chill" (104). "Melungeon Man" is a country music song and music of this genre tends to be based on real life events, feelings and emotions.