From The Art and Popular Culture Encyclopedia
Café society was the collective description for the so-called "beautiful people" and "bright young things" who gathered in fashionable cafes and restaurants in Paris, London, Rome or New York, beginning in the late 1800s. Lucius Beebe, noted American author, journalist, gourmand, and railroad enthusiast is generally credited with creating the term "café society," which he chronicled in his weekly column, This New York, for the New York Herald Tribune during the 1920s and 1930s.
Although members of café society were not necessarily members of The Establishment or other ruling class groups, they were people who attended each other's private dinners and balls, took holidays in exotic locations or at elegant resorts, and whose children tended to marry the children of other café society members.
In the United States, café society came to the fore with the end of Prohibition in December 1933 and the rise of photo journalism, to describe the set of people who tended to do their entertaining semi-publicly, in restaurants and night clubs and who would include among them movie stars and sports celebrities. Some of the American night clubs and restaurants frequented by the denizens of café society included El Morocco, the Stork Club, the 21 Club, and the Pump Room.
In the late 1950s the term "Jet Set" began to take the place of "café society", but "café society" may still be used informally in some countries to describe people who habitually visit coffeehouses and give their parties in restaurants rather than at home.