Caudle-cups are generally made exclusively in the 17th century and are sometimes decorated with royal portraits or the arms of guilds. Lipski and Archer record fourteen dated examples with portraits of Charles II. A similar initialled cup with a portrait of Charles II is in the Victoria & Albert Museum, see Michael Archer, Delftware The Tin-Glazed Earthenware of the British Isles, London, 1997, p. 246, C.9. See also John C. Austin, British Delft at Williamsburg, Williamsburg, Virginia, 1994, p. 103, no. 86 for a related cup with William and Mary. The present example with a portrait of William III alone must be considered relatively rare.