Desi Sangye Gyatso (1653–1705) was the fifth regent (desi) of the 5th Dalai Lama (1617–1682), who founded the School of Medicine and Astrology on Chags po ri (Iron Mountain) in 1694 and wrote the Blue Beryl (Blue Sapphire) treatise. The name is sometimes written Sangye Gyamtso.
By some accounts, Sangye Gyatso is believed to be the son of the "Great Fifth". He ruled as regent, hiding the death of the Dalai Lama, while the infant 6th Dalai Lama was growing up, for 16 years. During this period, he oversaw the completion of the Potala Palace and warded off Chinese politicking. The discovery of his deception was not taken kindly by the Kangxi Emperor of the Qing dynasty.
He is also known for harboring disdain for Tulku Dragpa Gyaltsen. According to Lindsay G. McCune in her thesis (2007), Desi Sangye Gyamtso refers in his Vaidurya Serpo to the Lama as the "pot-bellied official" (nang so grod lhug) and states that, following his death, he had an inauspicious rebirth.,
The medical college at Chagpori (lchags po ri; "Iron Mountain") was designed for monastic scholars who would, after learning esoteric arts of medicine and tantrism, mostly remain in the monastery, serving the public as would other monk scholars and lamas.
Sangye Gyatso became regent or desi of Tibet at the age of 26 in 1679. Three years later, in 1682, the 5th Dalai Lama died. However, his demise was kept secret until 1696-97, and the desi governed Tibet.
It was only in 1697 that the Sixth Dalai Lama, Tsangyang Gyatso, was installed. This evoked great irritation from the Qing Kangxi Emperor who had been kept in the dark about the matter, and furthermore was an enemy of the Dzungar rulers. Meanwhile, a new and ambitious Khoshut ruler came to power, Lha-bzang Khan.
The murder of the desi
The Sixth Dalai Lama turned out to be a talented but boisterous young man who preferred poetry-writing and the company of young women to monastic life. In 1702 he renounced his monastic vows and returned to lay status but retained his temporal authority.
Lha-bzang Khan was a man of character and energy who was not content with the effaced state in which the Khoshut royal power had sunk. He set about to change this, probably after an attempt by Sangye Gyatso to poison the king and his chief minister.
This was opposed by the cleric Jamyang Zhépa from Drepung Monastery, the personal guru of Lha-bzang. Rather, the khan was strongly recommended to leave for Qinghai, the usual abode of the Khoshut elite. He pretended to comply and started his journey to the north.
However, when Lha-bzang Khan reached the banks of the Nagchu River northeast of Ü-Tsang, he halted and began to gather the Khoshut tribesmen. In the summer of 1705 he marched on Lhasa and divided his troops in three columns, one under his wife Tsering Tashi. When Sangye Gyatso heard about this he gathered the troops of Ü-Tsang, Ngari and Kham close to Lhasa. He offered battle but was badly defeated with the loss of 400 men.
The Lobsang Yeshe, 5th Panchen Lama tried to mediate. Realizing that his situation was hopeless, Sangye Gyatso gave up resistance on condition that he was spared and was sent to Gonggar Dzong west of Lhasa. However, the vengeful Queen Tsering Tashi arrested the ex-desi and brought him to the Tölung Valley, where he was killed, probably on 6 September 1705.