1102 - 1147 (45 years)
 | Sibyl Marshall 1209-1245 |
| Sibyl Marshall | |
| B: | 1209 |
| Pembroke, Pembrokeshire, Wales | |
| D: | 27 Apr 1245 |
| Pembroke, Pembrokeshire, Wales | |
| 5th Earl of Derby Sir William de Ferrers, III | |
| B: | 1200 |
| Derbyshire, England | |
| D: | 24 Mar 1254 |
| Evington, Leicestershire, England | |
 | Countess of Cornwall Isabel Marshall 1200-1240 |
| Countess of Cornwall Isabel Marshall | |
| B: | 9 Oct 1200 |
| Pembroke, Pembrokeshire, Wales | |
| D: | 17 Jan 1240 |
| Hertfordshire, England | |
 | 1st Earl of Cornwall Richard Plantagenet 1209-1272 |
| 1st Earl of Cornwall Richard Plantagenet | |
| B: | 5 Jan 1209 |
| Winchester, Hampshire, England | |
| M: | 30 Mar 1231 |
| Buckinghamshire, England | |
| D: | 2 Apr 1272 |
| Berkhamsted, Hertfordshire, England | |
| 4th Earl of Hertford and 5th Earl of Gloucester Gilbert de Clare, III | |
| B: | 1180 |
| Hertford, Hertfordshire, England | |
| M: | 9 Oct 1217 |
| D: | 25 Oct 1230 |
| St Laurent, Gironde, Aquitaine, France | |
| 4th Countess of Pembroke Isabella de Clare | |
| B: | Feb 1172 |
| Pembroke, Pembrokeshire, Wales | |
| D: | 14 May 1220 |
| Pembroke, Pembrokeshire, Wales | |
| 1st Earl of Pembroke William Marshall, the Elder | |
| B: | 12 May 1146 |
| Pembrokeshire, Wales | |
| M: | Aug 1189 |
| Tower of London, London, England | |
| D: | 14 May 1219 |
| Caversham, Oxfordshire, England | |
 | 2nd Earl of Pembroke, Lord of Leinster, and Justiciar of Ireland Richard FitzGilbert de Clare 1130-1176 |
| 2nd Earl of Pembroke, Lord of Leinster, and Justiciar of Ireland Richard FitzGilbert de Clare | |
| B: | 21 Sep 1130 |
| Tonbridge, Kent, England | |
| D: | 20 Apr 1176 |
| Pembroke, Pembrokeshire, Wales | |
| Princess of Leinster Aoife 'Eve' MacMurrough | |
| B: | 26 Apr 1145 |
| Ireland | |
| M: | 26 Aug 1171 |
| Waterford County, Ireland | |
| D: | 26 Aug 1188 |
| Waterford, Waterford, Ireland | |
| Isabel de Beaumont 1102-1147 |
| Isabel de Beaumont | |
| B: | 1102 |
| Leicester, Leicestershire, England | |
| D: | 6 Jan 1147 |
| Carmarthen, Carmarthenshire, Wales | |
| 1st Earl of Pembroke Gilbert FitzGilbert de Clare | |
| B: | 21 Sep 1100 |
| Tonbridge, Kent, England | |
| M: | 1130 |
| Tonbridge, Kent, England | |
| D: | 6 Jan 1148 |
We make every effort to document our research. There is a lot of information that I do not have, and I know there are mistakes in this tree. My feelings will not be hurt if you give me corrections or additional information, especially if you can provide sources for the information.
