| | | | | | | | Richard I Duke of Normandy d. 996 |
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| | | | | | | | Geoffrey Count of Eu d. 1015 |
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| | | | House of Clare | | Gilbert Count of Brionne and Eu d. 1040 |
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| | | | Richard fitz Gilbert Lord of Bienfaite, Orbec, Clare and Tonbridge, joint Chief Justiciar of England d. c. 1090 | | | | | | Baldwin FitzGilbert Lord of Sap and Meules, baron of Okehampton Sheriff of Devon d. 1090 |
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| | | | | | | | Robert fitz Baldwin | William fitz Baldwin baron of Okehampton Sheriff of Devon fl. 1096 | Richard fitz Baldwin baron of Okehampton Sheriff of Devon d. 1137 | Adelise fitz Baldwin eventual heiress | [? Matilda] fitz Baldwin m. William fitzWimund m. Ranulf Avenel |
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| Roger fitz Gilbert de Clare Lord of Bienfaite and Orbec d. 1131 | Gilbert fitz Richard de Clare Lord of Clare Tonbridge and Cardigan d. 1117 | Walter fitz Richard de Clare Lord of Netherwent d. c. 1138 | Richard fitz Richard de Clare Abbot of Ely | Robert fitz Richard Lord of Little, Dunmow (Essex) d. 1136 |
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Richard fitz Gilbert de Clare Lord of Tunbridge and Cardigan d. 1136 | Gilbert fitz Gilbert de Clare Earl of Pembroke d. 1148/1149 | Baldwin fitz Gilbert de Clare Lord of Bourne d. 1154/1166 | | Barons FitzWalter male line extinct 1431 | Daventry of Daventry male line extinct 1381 | Fawlsey of Fawlsey male line extinct 1392 | |
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Gilbert fitz Richard de Clare Earl of Hertford d. 1152 | Roger fitz Richard de Clare Earl of Hertford d. 1173 | Rohaise de Clare m. Gilbert de Gant Earl of Lincoln | Alice de Clare m. Cadwaladr ap Gruffydd Prince of Gwynedd | Lucy de Clare m. Baldwin de Redvers Earl of Devon | | Richard fitz Gilbert de Clare Strongbow Earl of Pembroke d. 1176 | |
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| Richard de Clare Earl of Hertford d. 1217 | Aveline de Clare d. 1164 m. Geoffrey fitz Piers Earl of Essex | | | | | | | Isabel de Clare m. William Marshal Earl of Pembroke d. 1220 | Gilbert de Clare of Striguil Earl of Pembroke d. 1185 |
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Mathilde de Clare m. Rhys Gryg Prince of Deheubarth d. 1234 | Gilbert de Clare Earl of Hertford and Gloucester d. 1230 | | Isabel Marshal coheiress of her mother | | | | other coheiresses |
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| | | Isabel de Clare d. 1264 | | Richard de Clare Earl of Hertford and Gloucester d. 1262 |
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| | | Bruce Kings of Scotland | Gilbert de Clare the Red Earl Earl of Hertford and Gloucester, Guardian of England d. 1295 | Bogo de Clare Clergyman d. 1294 | Thomas de Clare Lord of Thomond, Chancellor of Ireland d. 1287 |
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Gilbert de Clare Earl of Hertford and Gloucester d. 1314 | Eleanor de Clare m. Hugh Baron Despenser m. William de la Zouche | Margaret de Clare m. Piers Gaveston, Earl of Cornwall m. Hugh de Audley, Earl of Gloucester | Elizabeth de Clare m. John de Burgh m. Theobald de Verdun m. Roger, Baron d'Amory | Gilbert de Clare Lord of Thomond d. 1308 | Richard de Clare Lord Clare, Lord of Thomond d. 1318 | Maud de Clare m. Robert Baron Clifford m. Robert Baron Welles | Margaret de Clare m. Gilbert de Umfraville m. Bartholomew Baron Badlesmere |
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| | | | | | (coheiresses) | | | | | | | Thomas de Clare d. 1321 | | | (coheiresses) |