On the Fact that if the Battle of Mons Badonicus Took Place as Chronicled (Still a Sketchy Proposition in that the Precise Date and Place Remain Unknown) the Welsh Population of Briton Constitutes the Truest Descendants of Pre-Roman England In that it Was There Where the Fast Advancing Jutes, Angles and Saxons Were Finally Stopped (and Where the Legend of King Arthur Originated)

 Many of the Britons of course remained behind and intermarried with the invaders (the early Jutes, Angles, and Saxons initially came to Briton as mercenaries and it wasn't until many years later that the mass migration reached its height) while many of the Germanic people undoubtedly moved west. But there have to be at least a few pure Britons left there and hence this little mental exercise of mine.