English Nobility Figure. She was married to a knight, Hugh Swynford. After his death, Katherine was the mistress and true love of John of Gaunt, Duke of Lancaster and second son of King Edward III. He married Constance of Castile for purely political and dynastic reasons. He married Katherine after Constance died to legitimize their relationship and provide for their children. Although her children with John of Gaunt were born before they were married, the children were legitimized by King Richard The King declared the Beauforts to be legitimate under English Law, but not eligible to the royal succession (though this did not, ultimately, prevent Katherine's great-great grandson from being crowned as Henry VII). Katherine's children with John included: á John Beaufort (1372 to 1409) had two sons Henry, Earl of Somerset and John, Duke of Somerset who fathered Margaret Beaufort (mother of Henry VII). á Joan Beaufort (1397 to 1440) had as her second husband, Ralph Neville of Derby, 1st Earl of Westmoreland. Joan's daughter, Cicely, married Richard, Duke of York and was mother to Edward IV and Richard III. John and Katherine between them started the Tudor and Yorkist Royal Houses directly and most of the European Royal Houses can trace their origins back to them through intermarriage. They had fulfilled an ancient prophecy of Merlin: "thou shalt get kings though thou be none!" His (now obliterated) epitaph in the original St. Paul's, described her as " an extremely beautiful woman". Little is known of her apart from when her life touched John's. The less charitable chroniclers at Saint Albans and Saint Mary's Abbey, York describes her as "a witch and a whore", and "she-devil and enchantress". After John's death, Katherine returned and Lincoln, and died in May 1403. She was buried by the high altar in the cathedral. Her daughter, Joan was also buried there and her tomb, can be found if facing to the right of the altar. All the decoration and brasses of them were removed by the soldiers of Cromwell, thus her gravesite give no indication of her importance in English History.