Llywelyn ab Iorwerth was born circa 1173 to Iorwerth ab Owain (1145-1174) and Marared ferch Madog (-) and died 11 April 1240 of unspecified causes. He married Joan of England (1190-1236) 1205 JL .
Children
| Name | Birth | Death | Joined with |
| Gwladus Ddu (-1251) | 1251 | Reginald de Braose (?-1228) Ralph de Mortimer (bef1198-1246) | |
| Elen ferch Llywelyn (1207-1253) | |||
| Dafydd ap Llywelyn (c1215-1246) | |||
| Name | Birth | Death | Joined with |
| Margaret Ferch Llywelyn (c1202-aft1268) | 1202 | 1268 | John de Braose (c1197-1232) Walter III de Clifford (?-c1263) |
Footnotes (including sources)
| ‡ General |
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