Ieuan was of Pengwern. Mostyn (p. 29) states that although Ieuan was Owain Glyn Dŵr’s nephew, he seems not to have joined the rebellion. But Carr (pp. 147-148) states that Ieuan and his wife "were still in rebellion in 1406 when the men of Anglesey made their peace with Henry IV. His lands were forfeit to the lord of Chirk but he had obviously submitted by 1409 when the receiver of the lordship reported that they had been restored to him."
Events
Date of Birth: unknown.
Place of Birth: unknown.
Living: 1406, 1409, 1411, 1412, 1419, 1427, 1432.
Mostyn (p. 29), Carr (1975, p. 29).
(probable) Date of Death: 26 December 1448.
The date is given by Carr (1979, p. 141 fn). Mostyn (p. 29) states that Ieuan was presumably dead by about 1437, as “a poem of about this date indicates that his wife, the daughter of the Lord Ednyfed, was then a widow.”
Relationships
Father: Adda ab Iorwerth Ddu ab Ednyfed Gam.
This relationship is shown by Bartrum (Tudur Trefor 13). It is given by Mostyn (p. 29, citing Mostyn MS. pedigree, 1663; Dwnn ii, p. 308; N.L.W. MS. 1654 B, fo. 311; Harl. MS. 4181, fo. 135 D; Cae Cyriog MS., fo. 61), by Dwnn (2:308, 2:327), by Carr (1979, p. 138), and by Lloyd (4:146). Mostyn (p. 27) cites a record dated 26 March 1437 (C.R.R. (Mostyn), an. 1437) which names Ieuan’s father as Adda.
Mother: Isabel ferch Gruffudd Fychan ap Gruffudd.
This relationship is shown by Bartrum (Tudur Trefor 13). It is given by Mostyn (p. 29), by Dwnn (2:308), by Lloyd (4:146), and by Carr (1975 p. 369 chart). Dwnn (2:327) names her Lowri, [daughter] of Griffydd Vychan. Carr (1979, p. 147) notes that Owain Glyn Dŵr was Ieuan's maternal uncle.
Spouse: Angharad ferch Ednyfed ap Tudur ap Gronwy ap Tudur ap Gronwy ap Ednyfed Fychan.
This relationship is shown by by Bartrum (Tudur Trefor 13, Marchudd 13). It is given by Mostyn (p. 29), by Dwnn (2:308, 2:327), by Carr (1975, p. 5; 1979, p. 139; 2011, p. 165), and by Lloyd (4:146).
Children:
(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, Mostyn, and Carr (1975).)
Isabel ferch Ieuan married Gruffudd ab Ieuan ab Einion.
Ieuan Fychan ab Ieuan (died 1457) married Angharad ferch Hywel.
Llywelyn ab Ieuan.
Iorwerth “yn Iawn” ab Ieuan married Catrin ferch Llywelyn. Iorwerth was ancestor of the Edwards family of Plâs Newydd.
Rhys ab Ieuan.
Rhys is given as a son by Mostyn and Dwnn, but not by Bartrum.
Dafydd.
Madog.
References
Bartrum, Peter C., “Tudur Trefor 13”, and “Marchudd 13” in An Electronic Version of Welsh Genealogies AD 300-1500. [The sources Bartrum cites for Ieuan are: Peniarth 129 (61, 90, 102) -- a copy made about 1500 of a MS written about 1497 by Gutun Owain; Peniarth 137 (30, 122) -- a MS written in the early 1500s by ‘Syr’ Thomas ap Ieuan ap Deiews.]
Carr, Antony David. The Mostyn Family and Estate, 1200-1643 (PhD thesis, University of Wales, 1975).
Carr, A.D. “The Making of the Mostyns: the Genesis of a Landed Family” in Transactions of the Honourable Society of Cymmrodorion (1979), pp. 137-157.
Carr, A.D. Medieval Anglesey. (Anglesey Antiquarian Society, 2011) 2nd ed.
Dwnn, Lewys, and Samuel Rush Meyrick. “Moiston Hall”, in Heraldic visitations of Wales and part of the marches between the years 1586 and 1613 by Lewys Dwnn. (Llandovery: William Rees, 1846).
Lloyd, Jacob Youde William. The History of the Princes, the Lords Marcher and the Ancient Nobility of Powys Fodog and the Ancient Lords of Arwystli, Cedewen and Meirionydd. (London: T. Richards, 1881-1887).
Mostyn, the Right Hon. Lord, and T. A. Glenn. History of the Family of Mostyn of Mostyn (London: Harrison and Sons, Ltd., 1925).
Oman, Sandra. “Ieuan ab Adda” in Tree: Wales. Welsh Medieval Database Primarily of Nobility and Gentry.