No. They are part of English folklore. The knights of the round table are a romantisiced view of the middle ages, if there was a King Arthur then he might have been around in the dark ages, say before AD 700, but nothing is proven or known about him in fact. Camelot may have been in Wales, Cornwall or Somerset, but no one knows for certain if it existed at all. Myth & legend, but I guess it's a cracking yarn for all that.....