Family/Spouse: Sir Hugh Swynford. [Group Sheet] [Family Chart]

Katharine married John (Plantagenet), of Gaunt, 1st Duke of Lancaster on 13 Jan. 1396/97 in Lincoln Cathedral, Lincoln, Lincolnshire, England. John (son of Edward III (Plantagenet), King of England and Philippa (Avesnes), of Hainault) was born in March 1340 in St. Bavo's Abbey, Ghent, Belgium; died on 3 Feb. 1398/99 in Leicester Castle, Leicester, Leicestershire, England; was buried on 16 March 1398/99 in Old St. Paul's Cathedral, London, Middlesex, England. [Group Sheet] [Family Chart]

1. John (Beaufort), Earl of Somerset, Marquess of Dorset was born circa 1372; died on 16 March 1410.
2. His Eminence Henry (Beaufort), Cardinal Beaufort was born circa 1375; died on 11 April 1447 in Wolvesey Castle, Winchester, Hampshire, England; was buried in Winchester Cathedral, Winchester, Hampshire, England.
3. Lady Joan Beaufort died on 13 Nov. 1440 in Howden, Yorkshire, England; was buried in Lincoln Cathedral, Lincoln, Lincolnshire, England.