The Vaughan lineage traces back from an antiquary (historical genealogist) along a well researched family in Marioneth, Wales, to the great-grandfather of the famed king of Wales, Bleddyn. The ancestry of the kings mother continues on back into antiquity.
King Cadwgan at generation 27 had several mistresses and many illegitimate children. A Weaver descendant has done extensive research on the ancestry 21 generations on back from King Cadwgan to King Cunedda (Kenneth, b. abt 400), making it available on the web [click here]. David Nash Ford has published research on the earlier kings lineage eleven generations on back to the legendary gods of the Welsh people: Beli Mawr (the great, b. around 1 AD) and his son Afallach [click here]. I would reject the purely speculative continuations on back to Adam.