Nielsen Hayden genealogy
Family: Richard of Cornwall, King of the Romans / Isabel Marshal (F917)
m. 30 Mar 1231-
Father | Male
Richard of Cornwall, King of the Romans
Born 5 Jan 1209 Winchester Castle, Hampshire, England 
Died 2 Apr 1272 Berkhamsted, Hertfordshire, England 
Buried Hailes Abbey, Gloucestershire, England 
Married 30 Mar 1231 [1, 2] Fawley, Buckinghamshire, England [1, 2] 
Other Spouse Joan | F1235 Married Other Spouse (Unknown mistress of Richard of Cornwall) | F16965 Married Other Spouse Sancie | F878 Married 23 Nov 1243 Westminster Abbey, Westminster, Middlesex, England 
Father John, King of England | F1256 Group Sheet Mother Isabel of Angoulême, Queen Consort of England | F1256 Group Sheet
Mother | Female
Isabel Marshal
Born 9 Oct 1200 Pembroke, Pembrokeshire, Wales 
Died 17 Jan 1240 Berkhamsted, Hertfordshire, England 
Buried Beaulieu Abbey, Hampshire, England 
Other Spouse Gilbert de Clare | F2646 Married 9 Oct 1217 Father William Marshal | F5382 Group Sheet Mother Isabel de Clare | F5382 Group Sheet
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Sources - [S142] Royal Ancestry: A Study in Colonial and Medieval Families by Douglas Richardson. Salt Lake City, 2013.
- [S128] The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant ed. Vicary Gibbs, H. A. Doubleday, Duncan Warrand, Howard de Walden, Geoffrey H. White and R. S. Lea. 2nd edition. 14 volumes (1-13, but volume 12 spanned two books), London, The St. Catherine Press, 1910-1959. Volume 14, "Addenda & Corrigenda," ed. Peter W. Hammond, Gloucestershire, Sutton Publishing, 1998., date only.
- [S142] Royal Ancestry: A Study in Colonial and Medieval Families by Douglas Richardson. Salt Lake City, 2013.