is French for "half-world". The term derives from a play called , by Alexandre Dumas , published in 1855. The play dealt with the way that prostitution at that time threatened the institution of marriage. The was the world occupied by elite men and the women who entertained them and whom they kept, the pleasure-loving and dangerous world Dumas immortalized in the 1848 novel and its many adaptations. Demimondaine became a synonym for a courtesan or a prostitute who moved in these circles—or for a woman of social standing with the power to thumb her nose at convention and throw herself into the hedonistic nightlife. A woman who made that choice would soon find her social status lost, as she became . The 1958 film Gigi, based on a 1944 novella by Colette, vividly portrays the world of the demimonde near the end of its existence. Gigi's Aunt Alicia, a legendary courtesan now enjoying a wealthy retirement, trains her teenage niece in elegant manners and deportment and the value of jewels and tries to stir her interest in fashion, in order to prepare her for life in the demimonde, pleasing the gentlemen who will provide her with the means to live comfortably. For the men, the high life of the was isolated from the other world of wives and families and duties (if any). It embraced heavy drinking, drug use, gambling, attending the theatre and ballet and horse races, the pursuit of high fashion in every aspect of life—and, of course, sexual promiscuity. Lavish spending led to indebtedness; the promiscuity could, in the worst scenario, lead to disease. Historically, the height of the was encapsulated by the period known in France as (1871–1914), from the end of the Franco-Prussian War to the beginning of World War I. The twentieth century brought the rise of the New Woman, changing economies and social structures, as well as changing fashions and social mores, particularly in the aftermath of World War I. Prostitution and the keeping of mistresses did not disappear, but the label became obsolete as the 'half-world' changed. Women called Externally, the defining aspects of the demimonde were an extravagant lifestyle of fine food and clothes, often surpassing that of other wealthy women of their day with a steady income of cash and gifts from their various lovers. Internally, their lifestyle was an eclectic mixture of sharp business acumen, social skills, and