The Chinese call this group Xiao Hei Yi, meaning "small black Yi." They call themselves Neisu. The Chinese include the Xiao Hei Neisu as part of the official Yi nationality, a collection of 120 distinct ethnolinguistic groups. One scholar notes that there is "nothing in common between different Yi groups."
The Xiao Hei Neisu "were on the second tier of an ancient social stratum which evidently spanned the breadth of east-central Yunnan. Above them were the Greater [Da Hei] Neisu and below them were two slave classes of Gepo. Although the actual practice of slavery was lost long before Liberation, the Lesser [Xiao Hei] Neisu still retain a sense of distinct identity from the Greater Neisu and the Gepo, including a different dialect and different costume. In certain regions such as the common borders of Xiyi, Xinshao, and Wushan districts of Mile County, the Greater and Lesser Neisu, along with the Gepo can still be found living in very close proximity, suggesting the former nature of their distribution."
Many Yi groups believe the progenitor of their race was Ou-lang and that he invented hunting and agriculture. Today, many villages hold an annual ceremony to worship Oulang. It affords the people a chance to socialize, trade, and catch up with relatives who live in different areas.
The Xiao Hei Neisu are polytheists. In their worldview, the earth is controlled by good and bad spirits. They offer regular sacrifices of sheep to ensure that they do not cause offense to the spirits. French missionary Crabouillet in 1873 found the Yi often hired shamans to chase evil spirits away from their villages by chanting and banging drums. The shamans determined the future by studying the organs of sacrificed sheep.
A few Xiao Hei Neisu became Christians in 1998 after Chinese Christians were mobilized to take the gospel to them. Most of the members of this group, however, have never heard the name of Jesus Christ. The Christian ministry Gospel Recordings produced a tape in the Xiao Hei Neisu language in 1998. This audio recording will prove greatly beneficial in reaching the Xiao Hei Neisu since most of them are illiterate.