Events
Date of Birth: unknown.
Place of Birth: unknown.
Bartrum gives Iorwerth a number of 7 in his generational dating system, which implies a birth date of, very roughly, about 1230.
Living: 1276.
Mostyn (p. 21) states that Iorwerth was a juryman in an inquisition held in this year.
Date of Death: unknown.
Place of Death: unknown.
Relationships
Father: Griffri ap Heilin ap Cynferth.
This relationship is shown by Bartrum (Mael Maelinydd 1). Griffri is said to be a descendant of Rhodri Mawr.
Mother: Mallt ferch Einudd ap Llywarch.
This relationship is shown by Bartrum (Mael Maelinydd 1).
Spouse: Tangwystl ferch Gruffudd ab Ednyfed Chwith.
This relationship is shown by Bartrum (Mael Maelinydd 1).
Spouse: Alice ferch Hwfa.
This relationship is shown by Bartrum (Mael Maelinydd 1).
Children (by Tangwystl):
(Complete source citations for facts about the children on this page are currently outside of the scope of this project. Most information below comes from Bartrum.)
Gwen married Gruffudd ap Gruffudd Fychan.
Children (by either Tangwystl or Alice):
Efa married Ieuaf ap Llywelyn.
Gwladus married Iorwerth Foel.
References
Bartrum, Peter C., “Mael Maelienydd 1” in An Electronic Version of Welsh Genealogies AD 300-1500.
[The sources Bartrum cites for Iorwerth are: Peniarth 131 (124, 127, 131, 135), written by Gutun Owain about 1480; Peniarth 129 (67, 90), copied about 1500 from a 1497 MS by Gutun Owain; and Peniarth 127 (36, 161), written by Syr Thomas ap Ieuan ap Deicws between about 1510 and 1523.]
Mostyn, the Right Hon. Lord, and T. A. Glenn. History of the Family of Mostyn of Mostyn (London: Harrison and Sons, Ltd., 1925).