Story wise I'm asking! After the Kohms took over the place where did the defeated Yangs go to? The hills? Surely the Kohms would have gone after them! It's almost as if the Yangs had come from another territory after years in the wilderness to reclaim their ancient homelands! A bit like the British who were thrown out of Btitain and went to live in France (Brittany) and hundreds of years later their progeny returned with William The Conqueror to take back the lands of their forefathers!
JB
Your memory exaggerates. During the really dark and little known period from about 411 to 597 a number of Britons did emigrate to Armorica and make it Brittany while during the same era members of various Germanic tribes emigrated to the island of Great Britain and converted the southern part of it into Anglo-Saxon England, presumably fighting many battles with the Romano-Britons in the process.
Bu there is hardly proof that the presumably somewhat small percentage of the Romano-Britons who emigrated to Brittany did so because they were thrown out of Britain.
And no doubt only a tiny percentage of the Bretons in Brittany joined the forces of William the Invader, of which they formed only a rather small percentage. So it is hardly the case that the new Norman ruling class in England was entirely composed of the entire former ruling class of post Roman Britain. There would only be a tiny overlap between the former ruling class of sub Roman Britain and the ruling class of Norman England.