The term "Miao" gained official status in 1949 as a minzu (nationality) encompassing a group of linguistically related ethnic minorities in southwest China. This was part of a larger effort to identify and classify minority groups to clarify their role in national government, including: establishing areas of autonomous government and allocating the seats for representatives in provincial and national government.
Though the Miao themselves use various self-designations, the Chinese traditionally classified them according to the most characteristic colour of the women's clothes. The list below contains the self-designations, the colour designations and the main regions inhabited by the four major groups of Miao in China:
- Ghao Xong; Red Miao; west Hunan.
- Hmu, Gha Ne (Ka Nao); Black Miao; southeast Guizhou.
- A-Hmao; Big Flowery Miao; northwest Guizhou and northeast Yunnan.
- Gha-Mu, Hmong, White Miao, Mong, Green Miao, Small Flowery Miao, Blue Miao; south Sichuan, west Guizhou and south Yunnan.
According to Chinese legend, the Miao who descended from the Jiuli tribe led by Chiyou (Chinese: 蚩尤 pinyin: Chīyoú) were defeated at the Battle of Zhuolu (Chinese: 涿鹿 pinyin: Zhuōlù, a defunct prefecture on the border of present provinces of Hebei and Liaoning) by the military coalition of Huang Di (Chinese: 黃帝 pinyin: Huángdì) and Yan Di, leaders of the Huaxia (Chinese: 華夏 pinyin: Huáxià) tribe as the two tribes struggled for supremacy of the Yellow River valley. According to legend, the battle, said to have taken place in the 26th century BC, was fought under heavy fog. The Huaxia, who possessed a form of mechanical compass, was able to defeat the tribe of Chiyou.
After general population movement toward south, southwest, and southeast (due in part to influx of northern and western groups such as Huaxia and Donghu), the tribe of Chiyou split into two smaller splinter tribes, the Miao and the Li (Chinese: 黎; pinyin: lí). The Miao continuously moving southwest and Li southeast as the Huaxia race, later known as Han Chinese, expanded southward. Some members of the Miao and Li tribes were assimilated into the Han Chinese during the Zhou Dynasty. (Recent DNA studies suggest that the movement of ethnic groups such as Miao in ancient East Asia is far more complex than this account.)
Another version of the story says that the tribe split three ways. It is said Chiyou had 3 sons, and after the fall of Jiuli, his eldest son led some people south, his middle son led some people north, and his youngest son remained in Zhuolu and assimilated into the Huaxia culture. Those who were led to the south established the San-Miao nation. Perhaps due to this splitting into multiple groups, many Far Eastern people regard Chiyou as their ancestors, and by the same token, many question the ethnicity of Chiyou as exclusively Mong or otherwise. In some circles of thought, the Koreans also regard Chiyou as an ethnic ancestor. Furthermore, under the present ethnic unification policy of the PRC, Chiyou is now also regarded as one of China's forefathers alongside the ethnic Han ancestors, Huangdi and Yandi.
According to the Miao burial ritual 'Show the Way', Miao history can be traced to as early as the Shang Dynasty (1600–1046 BC). After the fall of Shang to Zhou, then came the Chu. When Chu fell to Qin, the great migration began. Many remained and started the great revolt that helped found the Han Dynasty under Liu Bang. Miao culture greatly influenced the Western Han.
According to André-Georges Haudricourt and David Strecker, the Miao were among the first people to settle in present day China. They found that the Chinese borrowed a lot of words from the Miao in regard to rice farming. This indicated that the Miao were the first rice farmers in China. In addition, geneticists have connected the Miao to the Daxi Culture in the middle Yangtze River region. The Daxi Culture has been credited with being the first cultivators of rice in the Far East.
The study goes on to mentioned that the Miao (especially the Miao-Hunan) have some DNA from the Northeast people of China, but has origins in southern china.
Miao scholars also proposed that an intact female corpse found in 1972 in Changsa, Hunan could be a Miao woman, based on the drawings on the casket which are characteristic of Miao design, and except for a few minor illustrations on the top left, Miao scholars assert the rest of the intricate illustrations resembles Miao legends and folk stories.
During the Miao Rebellions (Ming Dynasty), when Miao tribes rebelled, Ming troops, including Han chinese, Hui people, and Uyghurs crushed the rebels, killing thousands of them. Mass castrations of Miao boys also took place.