To provide suporting evidence for the common descent of the various Anglo-Irish Devereux families from Robert Devereux, Archbishop of Rouen and Count of Evreux. This line is of special interest as the family claims common male ancestry with William the Conqueror, and potentially could provide the Y-chromosome pattern for the House of Normandy. Current testing has demonstrated patterns for several potential ancestral lines reaching back to the early 1700's in both Ireland and England, and some of these findings are consistent with Norman origins.