Katherine Swynford & John of Gaunt, Duke of Lancaster

Born in 1350, Katherine Swynford was the daughter of Sir Payne de Roet, a Flemish herald from County of Hainaut. At the age of sixteen, Katherine Swynford married "Hugh" Ottes Swynford, a knight from the manor of Kettlethorpe in Lincolnshire. She had three children with him: Blanche, Thomas, and Margaret. Hugh Swynford died sometime before she started her affair, but the specific year is not know. She originally worked for John of Gaunt as a governess for his two children, Philippa of Lancaster and Elizabeth of Lancaster. The Duke's wife, Blanche, had Katherine's daughter Blanche (her namesake) placed into the same chambers and allowed the same luxuries of her daughters. John of Gaunt also served as the godfather to her daughter Blanche.

After Blanche died from the plague in 1369, Katherine and John of Gaunt started a love affair that would produce four children out of wedlock. Their relationship endured through the Duke's second marriage to Infanta Constance of Castile, and after she died in 1396, the couple finally married in Lincoln Cathedral. Unfortunately their marriage only lasted three years. John of Gaunt died three years later in 1399. Katherine outlived him by four years. Their four children are John Beaufort, Henry Beaufort, Thomas Beaufort, and Joan Beaufort.

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