Late 19 Century, there was a Communist Party Movement Project called "Ethnic Identification" to form the Ethnic groups in China. Due to the many Ethnic groups during that time, many of the groups that had somewhat similar in culture, traditional, and language dialect have to merge into the big group. The name "Miao" is a name that combined the many Hmong groups in China.
Watch (Final) Episode 3 on Hmong failed to form Hmong Province in China and the starting of Hmong Education in China and watch Episode 1 on Hmong population in China.
Source: http://www.shrdo.com/
