One of the Four Great Ancestral Clans along with Se, Mu and Dong (and Five Great Ancestral Clans if Zhingbo Go is included). According to the Treasury of the Ancestral Clans of Tibet, also known as Dri, Achak Dri and Chakmo. The clan spread widely in Kham. According to the 15th century bshad mdzod chen mo, the four princely lines of Tong trace their ancestry to an unknown male ancestor and a female ancestor named Nemen Gyelmo (ngas sman rgyal mo). The Tong splits into 8 subdivisions: dmar or mar, dmar ma, snyal or gnyal, snyal dbyen, sngog or rngog or rngogs, khrog, rtog, and bas, sba, rba, sbas or dba’s.