The Duchess of Portsmouth was the least popular mistress of this "Merry Monarch" (& that was quite a contest)
... subtle daughter of Brittany, Louise de KeroualleDuchess of 
Portsmoutha ... Davis, whom Charles picked out of a coffee-house, and far less 
than Madam... [DOC] [TLE] Amazon.com: The French Mistress: A Novel of the Duchess of ... [PAR] Editorial Reviews.