Events
Date of Birth: unknown.
Place of Birth: unknown.
Date of Death: shortly before 1 April 1292.
Place of Death: unknown.
The date is given by Cavell (2005, p. 178).
Place of Burial: Haughmond Abbey.
The place is given by Cavell (2005, p. 178).
Relationships
Father: Roger (III) de Mortimer, lord of Wigmore.
This relationship is given by Crump (ODNB), by Lieberman (p. 91), by Cavell (2007, p. 75), and by the Complete Peerage (1:240).
Mother: Maud de Briouze.
This relationship is given by Crump (ODNB), by Lieberman (p. 91), by Cavell (2007, p. 75), and by the Complete Peerage (1:240).
Spouse: John (III) FitzAlan.
This relationship is given by Crump (ODNB), by Lieberman (p. 91), by Cavell (2007, p. 62), and by the Complete Peerage (1:240).
Spouse: Robert de Hastings.
This relationship is by the Complete Peerage (1:240). The marriage is supposed to have taken place 2 September 1285 at Poling in Sussex.
Children (by John):
Richard (3 February 1267 - 9 March 1302), earl of Arundel, married Alasia di Saluzzo.
Matilda married (1) Philip Burnell; married (2) Robert (VI) de Brus; married (3) Simon Criketot.
References
Cavell, Emma. "Aristocratic Widows and the Medieval Welsh Frontier: The Shropshire Evidence: The Rees Davies Prize Essay" in Transactions of the Royal Historical Society, Sixth Series, Vol. 17 (2007), pp. 57-82.
Cavell, Emma. "The Burial of Noblewomen in Thirteenth-Century Shropshire" in Thirteenth Century England XI (2005).
Cokayne, George Edward, and Vicary Gibbs; et al. The complete peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, extant, extinct, or dormant [2nd ed.]. (London: St. Catherine Press, 1910-59).
Crump, J.J. “Mortimer, Roger (III) de, lord of Wigmore (1231-1282)” in the Oxford Dictionary of National Biography (Oxford University Press, 2004).
Lieberman, Max. The Medieval March of Wales (Cambridge University Press, 2010).
Mortimer, Ian. "The Medieval Mortimer Family: An outline lineage". Accessed 17 August 2019.
Richardson, Douglas. A post to soc.genealogy.medieval dated 4 March 2016. (Richardson shows that a marriage often given, of Isabel to Ralph d'Arderne, is actually of a different Isabel.)
Tout, T.F. “Fitzalan, Richard (I), first earl of Arundel (1267 - 1302)” rev. Nigel Saul, in the Oxford Dictionary of National Biography (Oxford University Press, 2004).