The outfit that became the qipao, the sijigiyan, was the traditional ethnic clothing of the Manchu, who took over China in 1644 and established their own Qing Dynasty as its rulers. In the process, they mandated that all adult Chinese men in service of the throne wear Manchu garb -- turning the loose-fitting straight-line sijigiyan, known in Mandarin Chinese as the changpao, into both a symbol of elite status and a stamp of absolute Manchu domination.
Eventually, the practice of wearing changpao became common even among non-Manchurian Chinese men who weren't part of the government. But non-Manchurian Chinese women continued to wear typical Chinese outfits -- usually blouses and long skirts under loose coats or jackets -- until the Qing Dynasty fell in 1911.
At that time, under the newly founded Republic of China, Chinese feminists called for women to end the practice of footbinding, cut their hair short and began wearing changpao as a means of asserting their equality with men.
By the 1930s, in colonial Shanghai and Hong Kong, the traditional Manchu male outfit had become feminized and stylized: The long gown was cut short and shaped to fit women's curves, elaborately printed or embroidered and turned into the dress commonly referred to as the qipao. Today, Chinese women who aren't restaurant staff or flight attendants do not wear the modern version of the qipao -- skin-tight, with a revealing leg slit and a hemline above the knee -- for anything other than weddings and gala events.
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