Washington's genealogy

One site has George Washington's genealogy all the way back to this one:

William de Washington


M, #321952, b. circa 1180, d. after 1220

William de Washington was born circa 1180. He was the son of Patrick fitz Dolfin and Derdere (?). He died after 1220

He was also known as William de Hertburn. He lived at Washington, County Durham, England.