<P> By the turn of the 20th century, full evening dress consisted of a black tailcoat made of heavy fabric weighing 16 - 18 oz per yard . Its lapels were medium width and the white shirt worn beneath it had a heavily starched, stiff front, fastened with pearl or black studs and either a winged collar or a type called a "poke", consisting of a high band with a slight curve at the front . After World War I, the dinner jacket became more popular, especially in the US, and informal variations sprung up, like the soft, turn - down collar shirt and later the double - breasted jacket; relaxing social norms in Jazz Age America meant white tie was replaced by black tie as the default evening wear for young men, especially at nightclubs . According to The Delineator, the years after World War I saw white tie "almost abandoned". But it did still have a place: the American etiquette writer Emily Post stated in 1922 that "A gentleman must always be in full dress, tail coat, white waistcoat, white tie and white gloves" when at the opera, yet she called the tuxedo "essential" for any gentleman, writing that "It is worn every evening and nearly everywhere, whereas the tail coat is necessary only at balls, formal dinners, and in a box at the opera ." </P> <P> It also continued to evolve . White tie was worn with slim - cut trousers in the early 1920s; by 1926, wide - lapelled tailcoats and double - breasted waistcoats were in vogue . The Duke of Windsor (then Prince of Wales and later Edward VIII) wore a midnight blue tailcoat, trousers and waistcoat in the 1920s and 1930s both to "soften" the contrast between black and white and allow for photographs to depict the nuances of his tailoring . The late 1920s and 1930s witnessed a resurgence in the dress code's popularity, but by 1953, one etiquette writer stressed that "The modern trend is to wear' tails' only for the most formal and ceremonious functions, such as important formal dinners, balls, elaborate evening weddings, and opening night at the opera". </P> <P> White tie is rarely worn in the early 21st century . When the Costume Institute Gala announced a white tie dress code in 2014, a number of media outlets pointed out the difficulty and expense of obtaining traditional white tie, even for the celebrity guests . Nevertheless, it survives as the dress code for royal ceremonies, debutante balls, and a select group of other social events in some countries . The male form has also been adopted for some formal weddings . In Britain, it is worn at some state dinners and certain May and commemoration balls at Oxford and Cambridge universities as well as University College Durham and St Andrews . It was the dress code for the Lord Mayor of London's Mansion House banquet until 1996, although David Cameron has worn white tie to the event as Prime Minister . In the US, white tie is worn at some state dinners, including the one held for Elizabeth II in 2007 . The Vienna Opera Ball and the Nobel Prize ceremony in Sweden are white tie events; in Scandinavia and the Netherlands, it is the traditional attire for doctoral conferments and is prescribed at some Swedish and Finnish universities, where it is worn with a doctoral hat . </P> <P> Prior to World War II formal style of military dress was generally restricted to the British, British Empire and United States armed forces; although the French, Imperial German, Swedish and other navies had adopted their own versions of mess dress during the late nineteenth century, influenced by the Royal Navy . </P>

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