According to Tibetan historical records such as Chronicle of Yongbula Kangzhi and Origin of Ou Di, Nie Chizamp was born in Bomi, Tibet, and was exiled by his family because of his strange appearance and strong personality. When he traveled in the Yalong River valley, he met 12 Yongben (Tibetan primitive Buddhism) who represented the interests of local tribes and was elected king.
Later, Nie Chizamp nationalized the surrounding small states, divided them into different grades, and preached "Yong Zhong Ben Jiao". Since then, the Tibetan people have broken through the clan barrier formed by consanguinity and started to divide ethnic groups by region.
This was around 360 BC.