Paris takes its fashion very, very seriously. So seriously, in fact, that wearing the wrong thing has actually caused a riot.
In 1911, two rival Parisian couture houses launched their "trouser skirts," an innovation in fashion that trod the very fixed line between the genders and seemed to promise greater flexibility for women in general. There were two different versions of the trouser skirt: One was a sort of baggy pant with a very low hanging crotch, described as "a sack with holes made for the legs to go through," not unlike the fashions on high streets today, and the other a pair of the same kind of pants topped with an over-skirt, again, not unlike high street fashions of today. Both versions were launched by models at the opening day of racing season to general revulsion and disgust, but thankfully, no violence.
It wasn't until the ladies attempted to promenade their future fashions on the boulevards that the fisticuffs started—at the Place de l'Opera, the poor models were attacked by a jeering mob of fashion Philistines, who pulled their hair, trampled their hats, and reduced them to tears. A squad of police officers on bicycles were dispatched to rescue the girls and escort them to safety.