Nielsen Hayden genealogy
Descendants of Diarmait mac Murchada, King of Leinster
Abt 1110 - 1171 (~ 61 years)Father: Donnchad mac Murchada, King of Leinster and Dublin ( - 1115)
Mother: Orlaith ingen Ua Braenain
Diarmait mac Murchada, King of Leinster (Abt 1110 Leinster, Ireland - 1 Jan 1171)
Mor ni Tuathail (Abt 1114 Castledermot, Kildare, Ireland - 1191 Ireland)
   └─ 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)
           │ + William de Briouze (of Abergavenny, Monmouthshire, Wales - 2 May 1230)
           │ + Warin de Munchensy (of Winfarthing, Norfolk, England - Abt 20 Jul 1255)(m. Aft 14 May 1219)
           ├─ Walter Marshal ( - 24 Nov 1245 Goodrich Castle, Herefordshire, England)
           │ + Margaret de Quincy (Bef 1217 - Bef 30 Mar 1266 Hampstead, Middlesex, England)(m. Jan 1242)
           ├─ William Marshal (Abt 1190 - 24 Apr 1231 bur.New Temple Church, London, England)
           │ + Eleanor of England (1215 - 13 Apr 1275 Montargis Abbey, Loiret, France)(m. 23 Apr 1224)
           ├─ Maud Marshal, Marshal Of England (1192 - 27 Mar 1248 bur.Tintern Abbey, Monmouthshire, Wales) =>
           │ + Hugh II le Bigod ( - Between 11 Feb 1225 and 18 Feb 1225)(m. 1207)
           │ + William de Warenne (of Lewes, Sussex, England - 27 May 1240 London, England)(m. Bef 13 Oct 1225)
           ├─ Isabel Marshal (9 Oct 1200 Pembroke, Pembrokeshire, Wales -
           │ 17 Jan 1240 Berkhamsted, Hertfordshire, England) =>
           │ 17 Jan 1240 Berkhamsted, Hertfordshire, England) =>
           │ + Gilbert de Clare (Abt 1180 - 25 Oct 1230 Penrose, Brittany, France)(m. 9 Oct 1217)
           │ + Richard of Cornwall, King of the Romans (5 Jan 1209 Winchester Castle, Hampshire, England - 2 Apr
           │ 1272 Berkhamsted, Hertfordshire, England)(m. 30 Mar 1231 Fawley, Buckinghamshire, England)
           │ 1272 Berkhamsted, Hertfordshire, England)(m. 30 Mar 1231 Fawley, Buckinghamshire, England)
            + William de Ferrers (Abt 1193 of Tutbury, Burton-on-Trent, Staffordshire, England -
            24 Mar 1254 Evington, Leicestershire, England)(m. Bef 14 May 1219)
            24 Mar 1254 Evington, Leicestershire, England)(m. Bef 14 May 1219)