For half a century, New Orleans' fantastic Mardi Gras balls were strictly for the upper crust. Nobody without money, blue blood, or both gained membership in the secret men's clubs or "krewes"* which staged them. Before 1900 there were only five clubs: Comus, Momus, Twelfth Night, Rex and Proteus. They culled guest lists with pernickety care, asked only the fairest of debutantes to serve as carnival queens. But times changed. The socially ambitious began forming their own krewes.
In 1928 New Orleans had 16 Mardi Gras balls. In 1946 there were 36. This year, a record-breaking total of 49 are being...