Genealogists question the validity of the several lists of companions of William, Duke of Normandy, at the Battle of Hastings 1066. The lists in question include the "Falaise Roll" and the "Battle Abbey Roll". The list below is of those proven to be at Hastings: 

From The Complete Peerage, vol. XII, postscript to Appendix L (regarding the 1066 Battle of Hastings), "Companions of the Conqueror," pp. 47-48: 

   1.Robert de Beaumont, later first Earl of Leicester. 
   2.Eustace, Count of Boulogne. 
   3.William, afterwards third Count of Evreux. 
   4.Geoffrey of Mortagne, afterwards Count of Perche. 
   5.William Fitz Osbern, afterwards first Earl of Hereford. 
   6.Aimeri, Vicomte of Thouars. 
   7.Hugh de Montfort, seigneur of Montfort-sur-Risle. 
   8.Walter Giffard, seigneur of Longueville. 
   9.Ralph de Toeni, seigneur of Conches. 
  10.Hugh de Grandmesil, seigneur de Grandmesnil. 
  11.William de Warenne, afterwards first Earl of Surrey. 
  12.William Malet, seigneur of Graville. 
  13.Eudes, Bishop of Bayeux, afterwards Earl of Kent. 
  14.Turstin Fitz Rou. 
  15.Engenulf de Laigle, seigneur of Laigle. 
  16.Geoffrey de Mowbray, Bishop of Coutances. 
  17.Robert, Count of Mortain, afterwards first Earl of Cornwall. 
  18.Wadard, believed follower of Bishop of Bayeux 
  19.Vital, believed follower of Bishop of Bayeux. 
  20.Goubert d'Auffay, seigneur of Auffay. 

Notes: 

1-12 recorded by William of Poitiers 
13 portrayed in battle scene on Bayeux Tapestry 
14-15 named by Orderic 
 16-20 were certainly in the Duke's army and almost certainly at the battle, with 16 named by
William of Poitiers, 17-19 portrayed in the Bayeux Tapestry, 20 said by
Orderic to have taken part in the English war before William became king. 

This information came from soc.genealogy.medieval 9/14/96.