John of Gaunt

== Marriages and family ==
John was married three times. His first wife, Blanche of Lancaster, was also his third cousin; both were great-great-grandchildren of King Henry III. They married in 1359 at Reading Abbey. They had seven children; only three survived to adulthood.

After Blanche's death in 1368, shortly after the birth of her last child, John married, in 1371, Infanta Constance of Castile, daughter of King Peter of Castile, giving him a claim to the Crown of Castile. They had one daughter. Constance died in 1394.

During his second marriage, some time around 1373 (the approximate birth year of their eldest son, [[John Beaufort, 1st Earl of Somerset|John Beaufort]]) John of Gaunt entered into an extra-marital love affair with Katherine Swynford, the daughter of an ordinary knight, which would produce four children for the couple. All of them were born out of wedlock, but were legitimised upon their parents' eventual marriage. The adulterous relationship endured until 1381, when it was ended out of political necessity.<ref>{{cite book |last=Weir |date=2008 |first=Alison |title=Katherine Swynford: the story of John of Gaunt and his scandalous duchess |place=London |author-link=Alison Weir }}</ref>

On 13 January 1396, two years after the death of Constance of Castile, Katherine and John of Gaunt married in [[Lincoln Cathedral]]. Their children were given the surname "[[House of Beaufort|Beaufort]]" after a former French possession of the duke. The Beaufort children, three sons and a daughter, were legitimised by royal and papal decrees after John and Katherine married. A later proviso that they were specifically barred from inheriting the throne—the phrase ''{{lang|la|excepta regali dignitate}}'' ("except royal status")—was inserted with dubious authority by their half-brother Henry IV. However as historian and author Nathen Amin points out there was no parliamentary ratification of this scribbled in amendment. Further testing and analysis on these three words is required to determine when exactly they were added. There is every possibility they were added as a later proviso during the height of the Wars of the Roses as a means to discredit any heirs of Margaret Beaufort.