Well, not “Welsh” but Brythonic. The Anglo-Saxon royal dynasty called the “House of Wessex” was supposedly founded by a certain Cerdic. The interesting thing about this character is that his name is Brythonic in origin, and of course that he defeated a Brythonic king to take his territory.
Now if we skip a few centuries to when the Anglo-Normans invaded Ireland, the Norman mercenaries were invited by a certain deposed Irish king – Diarmait Mac Murchada. A not uncommon solution for a king having been deposed was to try and raise an army to take the kingdom back, and if you have plenty of cash, mercenaries may well be part of that army.
There is no evidence for this, but what if Cerdic was a deposed Brythonic king, or a disgruntled Brythonic noble who hired a bunch of germanic mercenaries. And if he had offered them land as well as gold, that could easily explain how a bunch of Saxons ended up living here.
Which may go some way to explaining why the Brythonic people didn’t really disappear but got absorbed over the centuries.
It’s a crazy idea and there’s no evidence for it. But it’s an interesting hypothesis.
