140px-House of Percy
The House of Percy (old French Perci) were a noble family in northern England for much of the Middle Ages, having descended from William de Percy who crossed from Normandy to England with William I in early December 1067 and was rebuilding York Castle in 1070. The name derives from the village of Percy-en-Auge in Normandy, the home of the family at the time of the Norman Conquest.Members have held the titles of Earl of Northumberland or Duke of Northumberland to this day, in addition to Baron Percy and other titles. In common with their rivals, the House of Neville, the Percy surname was twice adopted through marriage to an heiress. In the 12th century, the original Percy line was represented by Agnes de Percy, Baroness Percy, whose son by Joscelin of Louvain retained the Percy surname. Again in the 18th century, heiress Elizabeth Percy married Sir Hugh Smithson, who adopted the surname Percy and was created Duke of Northumberland.