Gyeltsen Bum (rgyal mthan 'bum) was born in late fifteenth century in Derge (sde dge). He is counted as the head of the family in its thirty-second generation. His father was Botar Tashi (14th-15th cent.), the first king of Derge. He had a monk brother named Pelden Sengge (dpal ldan seng+ge), who was trained at Ngor Ewaṃ Choden (ngor e wa+M chos ldan) in Tsang, under the guidance of numerous masters, including Lhachok Sengge (lha mchog seng+ge,1468-1535), the ninth abbot of Ngor. Pelden Sengge is said to have founded a monastic institution named Nyin Gon (nyin dgon), possibly with the sponsorship of Gyeltsen Bum.
Gyeltsen Bum had four sons. The eldest, Ponchen A-nga (dpon chen A snga) governed the kingdom, while the other three sons became monks.
དཔྱད་གཞིའི་ཡིག་ཆ་ཁག།
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