Gwynn, Nell (–)English comedy actress, mistress of Charles II, who was one of the most popular figures of Restoration England. Name variations: Gwyn or Gwynne. Born Eleanor Gwynn on February 2, , in England (authorities are unsure whether in London, Oxford, or Hereford); died on Novem; daughter of Helena and Thomas or James Gwynn (a common soldier); children: (with.