Shamanism was first practiced by Siberian tribesman and later spread south to China, southwest to central Asia, and east across the Bering straits to North America. Hmong probably became shamanic during their sojourn in Siberia and continued to practice the religion when migrated to China; adopted by many other tribal groups and incorporated in the state religion by the early dynasties. According to the legend, Hmong’s First shaman is a prophet, named Shee Yee (Siv Yis). It is believed that Yawm Saub (God to the Hmong people) sent Shee Yee's down to Earth to cure the ill. Shee Yee married a Hmong woman & had a son. However, Ntxwv Nyoog, the God of Sickness and Death, killed Shee Yee's son. Shee Yee was very disappointed about the death of his son. Shee Yee felt bad that although he’s able to save people on earth and heaven, he was unable to save his own son. He decided to not perform shaman rituals (ua neeb) anymore and returned to heaven. However, he will spread his powers to earth by dividing his tools around the world, and only the selected few will get this power to cure others. He left, saying that “only the pure-hearted individuals will receive this special power.” Now, Shee Yee is watching from above at the individuals, whom he had let his special power down to.
Sources
THE BEGINNING OF SHAMANISM