For Wikipedia believer/follower, the history of Cheongsam,
so called traditional wear of Chinese once upon a time.
from text .....
"The modern version, which is now recognized popularly in China as the "standard" qipao, was first developed in Shanghai in the 1920s, partly under the influence of Beijing styles. People eagerly sought a more modernized style of dress and transformed the old qipao to suit their tastes. Slender and form fitting with a high cut, it had great differences from the traditional qipao. However, it was high-class courtesans and celebrities in the city that would make these redesigned tight fitting qipao popular at that time. In Shanghai it was first known as zansae or "long dress" (長衫—Mandarin Chinese: chángshān; Shanghainese: zansae; Cantonese: chèuhngsāam), and it is this name that survives in English as the "cheongsam".
try wiki it, google it.