Alys, Countess of the Vexin (4 October 1160 – c. 1220) was the daughter of King Louis VII of France and his second wife Constance of Castile. She is also known as Alaïs, Adélaïde, Adèle, Alais, or Alix, but is not to be confused with her half-sister Alix of France, the daughter of Louis by his first wife Eleanor of Aquitaine.
By 1177, this had become a scandal and a source of friction between England and France. In that year Cardinal Peter of St Chrysogonus, on behalf of Pope Alexander III, threatened to place England's continental possessions under an interdict if Henry did not proceed with Alys's marriage to his son. Henry eventually pacified Louis VII while still avoiding the central issue: Alys remained with Henry, unmarried. There were widespread rumours that he had made her his mistress and that she had a child by him. It was said of Alys that "except for her looks, the tales were none too good", as she was considered promiscuous throughout her life.
When King Henry died on 6 July 1189, her long-time fiancé, Richard, succeeded to the throne but terminated their engagement in Messina in March 1191, on the grounds that she had borne a child by his father. She was sent back to France in 1195.
Her brother, King Philip II of France, had offered her to Richard's younger brother Prince John in 1192, but Queen Mother Eleanor of Aquitaine put a stop to that. Instead Alys was married on 20 August 1195 to William III Talvas, Count of Ponthieu, and they had three daughters: Jean (born dead), Marie, Countess of Ponthieu, and Isabelle. Alys was still alive on 28 July 1218; the date of her death is unknown.
Alys has appeared in a number of historical novels. She has a minor role in Sharon Kay Penman's novel, Time and Chance. American author/poet Judith Koll Healey published the historical novel The Canterbury Papers (The Lost Letters of Aquitaine outside the US) in 2004. It depicts Alaïs later in life, after her return to France, and sends her on a mission to England to retrieve some letters from Canterbury Cathedral for Eleanor of Aquitaine.
Alys is a major character in James Goldman's play The Lion in Winter, in which she is depicted as Henry II's lover. She was played by Jane Merrow in the 1968 film adaptation, for which she was nominated for the Golden Globe Award for Best Supporting Actress - Motion Picture, and by Yuliya Vysotskaya in the 2003 TV adaptation.
She was also played by Katherine DeMille, adopted daughter of Cecil B. DeMille, in his 1935 film, The Crusades, by Susan Shaw in the British children's TV series Richard the Lionheart (1962), and by Lorna Charles (aged 13) and Lucy Gutteridge (as an older teenager and adult) in the BBC TV drama series The Devil's Crown (1978).