Postmodernism emerged after the 1950s, more precisely between 1960 and 1970 in America as a reaction to the formalized architectural “international style.” The style requires the introduction of specific forms where necessary, rather than the use of formal principles regardless of territory and location. Postmodernism is a neo-eclecticism that requires architecture not to conform to purely functional and economic requirements, giving rise to an architecture similar to that of Louis Sullivan in the 1920s, who directly calls himself a functionalist. The initiator of the movement is Robert Venturi (born 1925 in Philadelphia). Prominent names are Michael Graves, Charles Willard Moore, Santiago Calatrava, James Sterling. The style allows a very wide treatment of classic patterns in an eclectic spirit, most widely used in attractions in Las Vegas and New Orleans.