Events
Date of Birth: unknown.
Place of Birth: unknown.
Bartrum (Sandde Hardd 1) gives Iorwerth a number of 5 in his generational dating system, implying a birth date of, very roughly, about 1170.
Date of Death: unknown.
Place of Death: unknown.
Relationships
Father: Hywel ap Moriddig ap Sandde Hardd.
This relationship is shown by Bartrum (Sandde Hardd 1).
Mother: Gwladus ferch Gruffudd ap Meilir Eutun.
This relationship is shown by Bartrum (Sandde Hardd 1).
(possible) Spouse: Jane ferch Rhirid Foel ap Gruffudd.
This relationship is shown by Bartrum (Sandde Hardd 1). The evidence for it is much later pedigrees.
Children:
Gronwy married Gwenlian ferch Rhys ap Dafydd ap Maredudd Hen.
References
Bartrum, Peter C., “Sandde Hardd 1” in An Electronic Version of Welsh Genealogies AD 300-1500.
[The sources Bartrum cites for Iorwerth are: Peniarth 131 (102, 135, 131), written by Gutun Owain about 1480; Peniarth 129 (25), copied about 1500 from a 1497 MS by Gutun Owain; Peniarth 127 (26), written by Syr Thomas ap Ieuan ap Deicws between about 1510 and 1523; and Peniarth 176 (175) by Gruffudd Hiraethog (died 1564).]