William de Percy

William I (Willame) de Percy (d.1096/9), 1st feudal baron of Topcliffe in North Yorkshire, known as Willame als gernons, was a Norman nobleman who arrived in England immediately after the Norman Conquest of 1066. He was the founder of the powerful English House of Percy, Earls of Northumberland, and Dukes of Northumberland, a great historical House of England "that, like Caesar's, has been artificially preserved (twice) to the present time". The male line ended in 1174/5 on the death without male progeny of his grandson William II de Percy, but the surname "Percy" was re-adopted by the latter's younger grandson Richard de Louvain (d.1244), whose own "Percy" descendants again failed in the male line in 1670 on the death of Joceline Percy, 11th Earl of Northumberland, and was again re-adopted by the latter's great-grand-daughter's husband Sir Hugh Smithson, 4th Baronet (c.1714-1786), created Duke of Northumberland, whose descendants survive today.