• General Notes

  [large-G675.FTW]
  
  On the Percies: The founder of the family was a Danish chieftain, Manfred, who died in 880. His son, Galfred, was a general of Rollo's in Normandy. The next of importance would be William, who came with the Conqueror , and who was the first Lord Percy. He died in 1097. The descendants of his son, Alan, founded the Percies of Heyshott and William's son, Richard, founded the Percies of Dunsley. Of the Children of William II, only daughters survived and of these only one had children.  She married Josceline de Lovain, brother of Adeliza, second wife of Henry II. Josceline  changed his name to Henry de Percy and the line continued.
  
  G.E.Cokayne--Complete Peerage is a good source if you read the  footnotes.
  
  There may be other descents, but the following is a patrilineal (father-to-
  son-to-son) descent:
  
  Lambert I C of Louvain (-1015) m. Gerberga of Lower Lorraine
  Lambert II C of Louvain (-1062) m. Oda of Lower Lorraine
  Henry II C of Louvain (-1079) m. Adelaide von Betuwe
  Godfrey D of Brabant (-1139) = ??
  Joscelin de Louvain (-1180) m. Agnes de Percy
  Henry de Percy (-1198) m. Isabel de Bruns
  William de Percy (-1245) m. Ellen de Balliol
  Henry de Percy (1235-1272) m. Eleanor de Warenne
  Henry de Percy 1 B Percy (1273-1314) m. Eleanor de Arundel
  Henry de Percy 2 B Percy (-1352) m. Idoine de Clifford
  Henry de Percy 3 B Percy (-1368) m. Mary of Lancaster
  Henry de Percy 1 E Northumberland (1341-1408) m. Margaret de Neville
  Henry Percy (1364-1403) "Hotspur"
  
  Hope this helps.
  
  William Addams Reitwiesner
  wrei@@loc.gov
  
  Schwennicke (ed.) Europaische Stammtafeln, iii, 710-712, list from William de Percy, m. Emma de Port down to Henry de Percy m. Eleanor de Poynings.  However the third generation which you list is omitted.  I.e., the William who m. Adeliza de Clare is listed as son of Alan and Emma de Gant.

Details of William de Percy III's family with Alice de Clare