It is possible that the legendary Arthur, associated with the Welsh legends of the 10th century, is based on the historical figure who commanded a British force against the Saxons. According to the 9th-century historians, this Arthur defeated the Saxons at Mount Badon in 518 and died at Camlan in 537.
It seems that there was a war leader, whose name we do not know, who defeated the Saxons, checking their advance temporarily. In later years people remembered this leader with longing; "Oh, if we only had ... to lead us now". Eventually the name Arthur adhered to this folk memory, and his list of accomplishments grew. Arthur is in many ways greater because we do not know the truth; it can't get in the way of peoples' need to create a saviour who is waiting to come to their aid when times get tough.
The real Arthur may have been a man named Ambrosius Aurelianus, or perhaps his war leader, who defeated the Saxons in a major battle we know as Mount Badon, (which may possibly be South Cadbury, in Somerset) halting their advance for as long as forty years. In the end, however, the superior might and numbers of the Saxons and their allies were too much for the islanders, and Arthur's efforts became little more than a historical footnote. A terrifically romantic and exciting footnote though, for Arthur and his deeds were woven like a silk thread into the fabric of myth and legend in which Celtic storytellers delight.