Isabel de Mohun

Isabelle de Mohun

• Birth 1240 / 1255 Somerset, England Born at Dunster Castle
• Death 1280 (aged 39–40) England
• Burial Newenham Abbey Axminster, East Devon District, Devon, England
• Memorial ID 171875487

Family

• Parents: Reynold II de Mohun 1200–1258 & Isabel Ferrers (disputed)
• Spouse: Edmund Deincourt 1256–1326 (son of John Deincourt and Agnes Neville)
• Siblings: John I de Mohun, Alice de Mohun de Beauchamp 1228–1275, Lucy de Mohun 1232–1297

Children

1. John Deincourt, spouse unknown; father of William "2nd Baron Deincourt" (disputed) (see William Deincourt, 2nd Baron Deincourt)
2. Isabel Deincourt. Wife of William FitzWilliam
3. Margaret Deincourt. Wife of Robert Willoughby

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Disputed origins

https://www.wikitree.com/wiki/Deincourt-2

Douglas Richardson presents the argument that Sir Edmund's wife Isabell Mohun was actually the daughter of Sir Reynold de Mohun's son John (by Sir Reynold's first wife), who married a sister of Sir Reynold's second wife Isabell Ferrers:

"Maxwell Lyte's book, History of Dunster, states that Reynold de Mohun and Isabel de Ferrers had a daughter, Isabel, who married Edmund Deincourt. We know from other sources, though, that Isabel de Ferrers' issue failed in 1324, whereas it is certain that Edmund Deincourt's issue continued past that date.

"Since Edmund Deincourt's wife can't possibly be the daughter of Reynold de Mohun, a good alternative seems to be that she was the daughter instead of Reynold's son, John de Mohun, and his wife, Joan de Ferrers. This would still leave Edmund's wife as a Mohun and still give her a descent from William de Ferrers, 5th Earl of Derby. Moreover, the chronology works fine. Edmund Deincourt was born about 1250 (as per the Thurgarton Cartulary). As such, we should expect his wife to have been born in the period, 1250/1255, which is the exact time period when John de Mohun and his wife, Joan, were having children."[2]

Comments

”Except by the time of her birth John de Mohun had already been dead two years and Joan was remarried to Robert d'Aguillon.”

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https://www.stirnet.com/genie/data/british/mm4fz/mohun1.php#dau3

• (1) Reynold / Reginald de Mohun, 5th of Dunster (d 20.01.1257/8) m2. Isabel de Ferrers (d before 26.11.1260, dau of William de Ferrers, 5th Earl of Derby)
  • (H) Isabel de Mohun m. Edmund Deincourt of Blankney and Branston, 1st Lord (d 06.01.1326/7)

https://www.stirnet.com/genie/data/british/dd/deincourt1.php

• (i) Edmund Deincourt of Blankney and Branston, 1st Lord (d 06.01.1326/7) m. Isabel de Mohun (dau of Sir Reynold de Mohun of Dunster)
  • (a) John Deincourt (dvp)
  • (b) William Deincourt (d Stirling 23.06.1314)
  • (c) Margaret Deincourt (d before 25.03.1317) m. (by 1303) Sir Robert de Willoughby, 1st Lord of Eresby (d 1316)
  • (d) Joan Deincourt m. (1302) Sir Philip de Draycott, younger of Paynsley (dvp 1308)

Research Notes

Cutter, William Richard. Genealogical and Family History of Southern New York and the Hudson River (1913) Page 341: (IX) Sir Henry (3), son of Sir Robert (3) de Pierrepont, of Holme-Pierrepont, married Margaret Fitz Williams, daughter of Sir William Fitz William, of Elsley, Knight, and Maude, daughter of Edmund, Baron Deincourt.

References

• 1. Complete Peerage, v.4 pp.118 - 124 Archive.Org
• Fould, Trevor. The Thurgarton Cartulary. Paul Watkins, Stamford, 1994. p. cxiii. Table 1b: Deyncourt Main Branch. link
• 2. <Per this SGM post in 2002.>
• www.findagrave.com
• https://www.wikitree.com/wiki/Mohun-39
• https://our-royal-titled-noble-and-commoner-ancestors.com/p518.htm#...
• https://fmg.ac/Projects/MedLands/ENGLISHNOBILITYMEDIEVAL3D-K.htm (lists son John only)
• https://www.stirnet.com/genie/data/british/mm4fz/mohun1.php#dau3
• https://www.stirnet.com/genie/data/british/dd/deincourt1.php

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