Nielsen Hayden genealogy
Descendants of Cacht ingen Loigsig Ua Morda
Father: Loigsech Ua Morda, King of Loigsi ( - 1149)
Cacht ingen Loigsig Ua Morda
   └─ Mor ni Tuathail (Abt 1114 Castledermot, Kildare, Ireland - 1191 Ireland)
    Diarmait mac Murchada, King of Leinster (Abt 1110 Leinster, Ireland - 1 Jan 1171)
       └─ Eve of Leinster (Abt 1145 - Aft 1185 bur.Tintern Abbey, Monmouthshire, Wales)
        Richard "Strongbow" fitz Gilbert (Abt 1130 - Abt 20 Apr 1176 Dublin, Ireland)
        (m. Abt 26 Aug 1170 Waterford, Munster, Ireland)
        (m. Abt 26 Aug 1170 Waterford, Munster, Ireland)
           └─ Isabel de Clare (1173 - 7 Mar 1220 bur.Tintern Abbey, Monmouthshire, Wales) =>
            + William Marshal (Abt 1146 - 14 May 1219 Caversham, Oxfordshire, England)
            (m. Aug 1189 London, England)
            (m. Aug 1189 London, England)