Analysis of the marriage pattern of Abraham's ancestors indicates that Cain and Seth married the daugthers of a chief named Nok (Enoch or Enosh). Their brides named their first-born sons after their father, which is why both Cain and Seth have first-born sons name Enoch or Nok. This indicates that Cain and Seth married patrilineal cousins. The exclusive naming prerogative of royal cousin brides permitted them to name their first-born sons after their fathers. This prerogative did not pertain to half-sister brides such as Sarah.
If we read the story of Adam and Eve literally, we must conclude that they are the parents of Cain and Seth. However, the Genesis 4 and 5 material is about the cousin brides of Cain and Seth, whose father was Enoch or Nok. If we insist on a literal reading of Adam and Eve, we must conclude that Enoch was a contemporary of Adam and Eve. However, this is contrary to the biblical significance of Adam and Eve as "first parents" and therefore suggests the mythological nature of the Adam and Eve story. On the other hand, the persons named in Genesis 4 and 5 are historical persons. The ancients understood the difference between historical and mythological and regarded these as equally capable of conveying truth. So it is that both Adam and Enosh would be viewed as founding fathers. This is why the names Adam and Enosh are paralleled in Psalm 8, which in Hebrew reads:
What is Man (Enosh) that you are mindful of him,
the son of Man (ben Adam) that you care for him?
So who fathered Cain and Seth, if not Adam? Their father, Nok, would have been the half-brother of Cain's mother. Nok would have been the patrilineal cousin of a daughter of Set the Nubian.This means that Nok and Set were brothers and it suggests the 8th century B.C. Napatan rulers of Nubia who conquered Egypt. Set was a royal name among the Napatan Nubians.
Since both Cain and Seth are listed as rulers they were first-born sons. This means that their father had two wives, as did Abraham and all Abraham's ruler-priest ancestors. One of those wives would have been a cousin bride who named her first-born son after her father. Would that be the mother of Seth or the mother of Cain? I'd be willing to wager that the cousin bride was Seth's mother. Why? Because Cain came to the region of Nok in northern Nigeria from the east (Gen. 4:16). There is no traceable ancient name in eastern Nigeria like Cain (Kain, Kayan, or Qayan). On the other hand, the name Set is found among peoples living to the east of Nok in the Upper Nile or Nubia.
There is evidence for this in 1 Chronicles 1:50 which mentions an important Horite bride - Matred - which is equivalent to Menmaatre, the throne name of Seti I. Seti is a name associated with Piye which 1 Chronicles identifies with the "city of Pai" (1:50). Piye's son was called Hor. King Piye of Egypt installed a black granite falcon head image of Horus at his capital in Napata.