Arrival of the House of Wessex

In 519, a man called Cerdic landed on the southern coast of England with 5 ships and a band of Saxon adventurers. 1,500 years later his descendants still provide the monarchs of England.
http://historyofengland.typepad.com/blog/2010/12/episode-1-the-arrival-of-the-house-of-wessex.html
The bare facts:

• Cerdic landed in Hampshire (see the map below), and over 6 years fought a number of battles
• Cerdic broke British power at Cerdices Leag (now Netley Marsh) when he defeated Natanleod and his army of 5,000 men
• Cerdic is a British (Celtic) name, not Saxon. Was he British ?