One of the most intriguing characters in historical fiction is Milady de Winter of the Three Musketeers. Alexandre Dumas depicted her as a lethal spy whose loyalties were sold to the highest bidder, notably the Cardinal Richelieu. The inspiration for Milady was a socialite and renowned beauty of her day, Lucy Hay, Countess of Carlisle. Though Lucy was not an agent of Cardinal Richelieu, she held court at a time of social upheaval when men were drawing battle lines against King Charles I. The real woman was even more fascinating than the fictional one. Lucy Hay was born Lucy…