Duchess of York is the principal courtesy title held by the wife of the Duke of York. The title is gained with marriage alone and is forfeited upon divorce. Five of the fourteen Dukes of York either did not marry or had already assumed the throne prior to marriage, whilst two of the dukes married twice, therefore there have only ever been eleven Duchesses of York. These Duchesses have either given birth to females (not male heirs to the dukedom of York), or they have never had any children at all. It is said that the position of Duke and Duchess of York is cursed, because the title is created every time, or these women become queen consorts.
Lady Elizabeth Bowes-Lyon (1923–1936) – Known as "The Smiling Duchess," she ceased to be known as the Duchess of York when her husband succeeded to the throne as George VI following the abdication of his elder brother, Edward VIII.
Sarah Ferguson (1986–1996)-Considered a close friend of Diana, Princess of Wales, she was introduced to the second eldest son of Queen Elizabeth II, Prince Andrew, whom she married on 23 July 1986. Following their high-profile marriage and divorce, she became known as Sarah, Duchess of York (the proper address for divorced wives of peers). In addition, she lost the style of Royal Highness as well as all other dignities related to the title of British princess. It is also important to note that since their divorce, it is merely a courtesy style which she holds and is no longer THE Duchess of York (That would be the title accorded to any future wive of Prince Andrew), Therefore she is also not a peeress nor entitled to the style 'Her Grace'. If Sarah, Duchess of York remarries, any use of the style Duchess of York will be lost permanently.