The Spirit Catches You mentions a Hmong Wall, a smaller version of the Great Wall.
Whoever said the wall of China was built partially to keep the Hmong out is so so wrong. First of all, the Hmong from China are geographically located in Southern China. The great wall is in Northern China. I highly doubt that the Hmong traveled North to fight the Chinese.
"Their ancestors originated in southwestern China, in the provinces of Yunnan, Guizhou, Sichuan, and Hunan. For several thousand years, the central Chinese government dominated by Han Chinese basically left the Hmong (called Miao by the Chinese) alone, as long as they paid their tributes to the Chinese. However, the last dynasty in China, the Qing (1644-1911), founded by Manchus, followed a different policy. Qing armies and officials oppressed the Hmong, who rose in rebellion. In the early nineteenth century, this political persecution, along with increasing population pressure, led some of the Hmong to migrate southward into mainland Southeast Asia, where they settled in the mountainous regions of northern Burma, Thailand, Laos, and Vietnam." - Sucheng Chan, Hmong Means Free
http://www.hmongnet.org/publications/hmf-intro.htmlAs someone else stated above, those Hmong people with blue eyes and brown hair are purely albino.
The Southern Great Wall was built by the rulers of the Ming Dynasty as a military blockade against the Miao people of the south. In 2001, the wall underwent major restoration to restore it back to its former state.
Here is a mini-documentary about it:
Part 1:
http://www.youtube.com/v/uxrrR8r4JOE&rel=1Part 2:
http://www.youtube.com/v/RxqFdzV_yQk&rel=1Part 3:
http://www.youtube.com/v/NHpLHV6Bc6c&rel=1

