Edmund de Mortimer was the second son (first surviving son) and heir of Roger III Mortimer and Maud de Braose. He was aged 30+ in 1282 and 40+ in 1301 (so born c.1252-1261).
As a younger son, Edmund had been intended for clerical or monastic life, and had been sent to study at Oxford University. He was made Treasurer of York in 1265. But the sudden death of his elder brother, Ralph, in 1276, made him heir to the family estates.
Edmund returned in 1282 as the new Baron Mortimer of Wigmore and immediately became involved in Welsh Marches politics. Together with his brother Roger Mortimer of Chirk, John Giffard, and Roger Lestrange, he devised a plan to trap Llywelyn the Last. Edmund sent a message to Llywelyn telling him he was coming to Llywelyn's aid and arranged to meet with him at Builth. But Edmund's brothers secretly forded the river behind Llywelyn's army and surprised the Welsh. In the resulting battle Llywelyn was killed and beheaded. Edmund then sent his brother Roger Mortimer of Chirk to present Llywelyn's severed head to King Edward I of England. Edmund was Knighted at Winchester in 1283
He married circa 1285 to Margaret de Fiennes, daughter of Sir William (II) de Fiennes, second cousin of Eleanor of Castile, Queen of Edward I, by Blanche de Brienne (herself the granddaughter of John of Brienne by his third wife Berenguela of Leon).
They had the following children:
Matilda (Maud) m. Theobald II de Verdunii; was born about 1286, she died on 18 Sep 1312 in Alton, Staffordshire, England. She was buried on 9 Oct 1312 in Croxden Abbey, Staffordshire, England.
Roger, 1st Earl of March, died on 29 Nov 1330 (executed at Tyburn). He was born on 3 May 1287 and m: Joan de Geneville.
Hugh, Rector of old Radnor, was born about 1290.
Joan was born about 1292.
Walter, Rector of Kingston, was born about 1294.
Edmund, Rector of Hodnet, Treasurer of York Cathedral, was born about 1298.
John was born in 1300. He died on 3 Jan 1318, slain in a Joust by John de Leyburn.
Isolde (Iseude, Iswolde) was born about 1270, m. Hugh I de Audley (although FMG has her as the daughter of a mistress). She died in 1328. (see note below)
Margaret was born about 1296.
Elizabeth was born about 1302.
Eleanor (see note below)
He attended Parliament from 24 June 1295 (23 Edward I) to 2 June 1302 (30 Edward I), during which time he became Lord Mortimer.
Edmund was knighted by King Edward at Winchester, and served in the King's Gascony and Scottish campaigns. He was mortally wounded in a skirmish near Builth.
He died 17 Jul 1304 and was buried at Wigmore Abbey, Wigmore, Herefordshire, England.
NOTE: See MedievalGenealogy.org - Corrections and Additions to the Complete Peerage Vol. 9, p. 269-70 for proposed changes to this profile (not completed as of 11/16/18)
↑ 1.01.11.21.31.4 Doubleday, H.A. and Lord Howard de Walden, ed., The Complete Peerage or A History of the House of Lords and All Its Members From The Earliest Times, London: The St. Catherine Press, 1936. Accessed online at LDS, Vol. IX, pages 281-283.
Richardson, Douglas, Royal Ancestry, 2013. Vol. IV, p. 168-170.
G.E. Cokayne; with Vicary Gibbs, H.A. Doubleday, Geoffrey H. White, Duncan Warrand and Lord Howard de Walden, editors, The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant. New ed., 13 vols in 14 (1910-1959; reprint in 6 vols., Gloucester, U.K.: Alan Sutton Publishing, 2000). Vol. I, page 347.
Peter W. Hammond, editor, The Complete Peerage or a History of the House of Lords and All its Members From the Earliest Times, Vol. XIV: Addenda & Corrigenda (Stroud, Gloucestershire, U.K.: Sutton Publishing, 1998), page 52.
Weis, Frederick Lewis, Ancestral Roots of Certain American Colonists who Came to America Before 1700, 7th ed., Baltimore MD: Genealogical Publishing Co., Inc., 1992. Access online (search only) at GoogleBooks, Line 120, p.107.