Mangkar (mang dkar) is a north-south valley in western Tsang (gtsang), south of Lhatse. Mangkar means “many fortresses” in modern Tibetan, and may have initially meant “many encampments” (Davidson, p. 177). Drokmi Shakya Yeshe, the 11th century primary translator of the Hevajra tantra systems and master of literary classical Tibetan, established a monastic center of learning at Mugulung in the Mangkar Valley after returning from his studies in India (circa 1036).
One of the imperial administrative units was located in the Mangkar Valley because the trade routes from central Tibet to both central Asia and Nepal divide at Lhatse, just to the north of the Mangkar Valley. The valley is associated with the Dro, Kyungpo, and Khön clans. The association with the latter is especially clear as the persons who eventually founded the Khön-backed Sakya sect got their start in Drokmi’s translation center, Mugulung, which is in a branch valley of the Mangkhar valley.
Mangkhar is noted once in the Blue Annals. In chapter 4, Mangkar is mentioned in reference to Stonpa (ston pa), who is part of a Sakya (sa skya) hereditary lineage. Stonpa visits sister and brother teachers, Khon puwa (khon phu ba) and Lhaje ma (lha rje ma), at their residence is Mangkar pang gang (mang khar spang sgang) and receives teachings and presents from them. {R 237}
Ronald Davison’s Tibetan Renaissance, p. 174-176.
Blue Annals Chapter 4