On 21 September 1371, Edward III's fourth son, John of Gaunt, 1st Duke of Lancaster, married Isabella's older sister, Constance (d. 1394), who after the death of their father in 1369 claimed the throne of Castile. Isabella accompanied her sister to England, and on 11 July 1372, at about the age of 17, married John of Gaunt's younger brother, Edmund of Langley, 1st Duke of York, fifth son of King Edward III and Philippa of Hainault, at Wallingford, Oxfordshire, as part of a dynastic alliance in furtherance of the Plantagenet claim to the crown of Castile.[2] According to Pugh, Isabella and Edmund of Langley were 'an ill-matched pair'.[3]
In her will, Isabel named King Richard as her heir, requesting him to grant her younger son, Richard, an annuity of 500 marks. The King complied. However, further largesse which might have been expected when Richard came of age was not to be, as King Richard II was deposed in 1399, and according to Harriss, Isabella's younger son, Richard, 'received no favours from the new King, Henry IV'.[5]
Isabella died 23 December 1392, aged about 37, and was buried 14 January 1393 at the priory of the Dominicans at Kings Langley.[6] After Isabella's death, Edmund of Langley married Joan Holland, sister and co-heir of Edmund Holland, 4th Earl of Kent (9 January 1382 – 15 September 1408), with whom his daughter, Constance, had lived as his mistress (see above).[7]
Isabella and Edmund of Langley, 1st Duke of York, had three children:
Edward of Norwich, 2nd Duke of York (c. 1373 – 25 October 1415), who married firstly, Beatrice of Portugal, which marriage was annulled, and secondly, Philippa Mohun, third daughter of John Mohun, 2nd Lord Mohun (c. 1320 – 15 September 1375), and Joan Burghersh (d. 4 October 1404), daughter of Bartholomew de Burghersh (c. 1304 – 3 August 1355), 3rd Baron Burghersh. Edward served in numerous administrative offices and military campaigns during the reigns of Richard II, Henry IV and Henry V, and was slain at the Battle of Agincourt on 25 October 1415.[10]
^Pinches, John Harvey; Pinches, Rosemary (1974), The Royal Heraldry of England, Heraldry Today, Slough, Buckinghamshire: Hollen Street Press, ISBN0-900455-25-X
^Anthony Emery, Greater Medieval Houses of England and Wales, 1300-1500: East Anglia, Central England and Wales, Vol. 2, (Cambridge University Press, 2000), 240.
Pugh, T.B. (1988). Henry V and the Southampton Plot of 1415. Alan Sutton. ISBN0-8629-9541-8.
Richardson, Douglas (2011). Magna Carta Ancestry: A Study in Colonial and Medieval Families, ed. Kimball G. Everingham. Vol. II (2nd ed.). Salt Lake City. ISBN978-1-4499-6638-6.{{cite book}}: CS1 maint: location missing publisher (link)
For the tombs of Edmund of Langley and Isabella of Castile, see 'Friaries: King's Langley priory', A History of the County of Hertford: Volume 4 (1971), pp. 446–451.[1] Date accessed: 21 October 2012