1172 - 1220 (48 years)
 | John de Mohun, II 1248-1279 |
| John de Mohun, II | |
| B: | 1248 |
| Dunster, Somerset, England | |
| D: | 11 Jun 1279 |
| Dunster, Somerset, England | |
 | Alinora Petri 1252-1283 |
| Alinora Petri | |
| B: | 1252 |
| Breconshire, Wales | |
| M: | 1268 |
| Dunster, Somerset, England | |
| D: | Jan 1283 |
| Blagdon, Somerset, England | |
 | Joan de Ferrers Abt 1233- |
| Joan de Ferrers | |
| B: | Abt 1233 |
| Derbyshire, England | |
| D: | Addington, Surrey, England |
| Knight of Munster John de Mohun, I 1232-1253 |
| Knight of Munster John de Mohun, I | |
| B: | 1232 |
| Dunster, Somerset, England | |
| M: | Abt 1245 |
| Derby, Derbyshire, England | |
| D: | 1253 |
| Dunster, Somerset, England | |
 | 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 | |
| Marchioness of Montferrat Isabel de Clare | |
| B: | May 1240 |
| Tonbridge, Kent, England | |
| D: | 1271 |
| Lord of Inchiquin and Youghal - Lord of Thomond Thomas de Clare | |
| B: | 1245 |
| Tonbridge, Kent, England | |
| D: | 29 Aug 1287 |
| Clare County, Ireland | |
| Juliana FitzGerald 1263-1300 |
| Juliana FitzGerald | |
| B: | 1263 |
| Dublin, Ireland | |
| D: | 24 Sep 1300 |
| Clare County, Ireland | |
| 7th Earl of Gloucester, Earl of Clare, Earl of Hertford Lord Gilbert de Clare, IV | |
| B: | 2 Sep 1243 |
| Christchurch, Hampshire, England | |
| D: | 7 Dec 1298 |
| Monmouthshire, Wales | |
| Princess of England Joan of Acre Plantagenet | |
| B: | 1272 |
| Israel | |
| M: | 30 Apr 1290 |
| Westminster, London, England | |
| D: | 23 Apr 1307 |
| Clare, Suffolk, England | |
| Eighth Earl of Clare, Sixth Earl of Hertford, 6th Earl of Gloucester Richard de Clare, IV | |
| B: | 4 Aug 1222 |
| England | |
| D: | 14 Jul 1262 |
| Waltham, Kent, England | |
 | Maud de Lacy 1223-1289 |
| Maud de Lacy | |
| B: | 25 Jan 1223 |
| Lincoln, Lincolnshire, England | |
| M: | 2 Feb 1238 |
| D: | 10 Mar 1289 |
| Lincoln, Lincolnshire, England | |
 | 6th Lord of Annandale Robert de Brus, VI 1243-1304 |
| 6th Lord of Annandale Robert de Brus, VI | |
| B: | Jul 1243 |
| Annan, Dumfries-shire, Scotland | |
| D: | 4 Apr 1304 |
| Lochawe, Argyll, Scotland | |
 | Countess of Carrick Marjorie MacDuncan 1252-1292 |
| Countess of Carrick Marjorie MacDuncan | |
| B: | 1252 |
| Argyll, Scotland | |
| M: | 1271 |
| D: | 27 Oct 1292 |
| Argyll, Scotland | |
| Isabel de Clare 1226-1264 |
| Isabel de Clare | |
| B: | 8 Nov 1226 |
| Tewkesbury, Gloucestershire, England | |
| D: | 10 Jul 1264 |
| Cleveland Port, Yorkshire, England | |
| 5th Lord of Annandale Sir Robert de Brus, V | |
| B: | 1210 |
| Lochmaben, Dumfries-shire, Scotland | |
| D: | 31 May 1295 |
| Lochmaben, Dumfries-shire, Scotland | |
| 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 | |
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.
