Part of a seriesTibetan Buddhism
|Practices and attainment|
Ralpacan (Wylie: Khri-gtsug-lde-brtsan. Other transcriptions: Repalcan, Relpachen, Tritsu Detsen or Tri Ralpachen), born c. 806, the Year of the Dog was, according to traditional sources, the 41st King of Tibet, ruling from the death of his father, Sadnalegs, in c. 815, until 838 CE. He is referred to as the 'Son of God' in the dBa' bzhed.
He was the second of five brothers. The eldest, Lhasras gTsangma, took Buddhist vows. The third, Langdarma, who was anti-Buddhist and ruled after the death of Ralpacan, is referred to in the sources as "unfit to reign". The younger two brothers both died young.
Ralpacan is considered very important to the history of Tibetan Buddhism as one of the three Dharma Kings (chosgyal) — Songtsän Gampo, Trisong Detsen, and himself — who brought Buddhism to Tibet. Trisong had five wives, all from Tibetan noble families.
Political activities 
The Tibetan Empire reached its greatest extent under his rule, and included parts of China, India, Nepal, Khotan, sBalti (Baltistan), Bruzha (Gilgit and Hunza), Zhang Zhung, Hor-yul, Sog-yul, Yugur, and Kamilog (roughly = present-day Sichuan), as well as almost all of modern Xinjiang and Gansu.
Ralpacan's power was aided by the able military leadership of Zhang 'Bro sTag. In 810 the Chinese Emperor wrote asking for the return of three prefectures. In 816 Zhang 'Bro sTag led a raid led to within two days journey from the Uyghur capital at Ordu Baliq. In 819 he attacked the Chinese town of Yanzhou, in the southern Ordos, close to the Great Wall, when he was referred to as "First Minister". During the negotiations for a peace treaty in 821 he led a violent attack against the Chinese, which may have contributed to Chinese willingness to make peace.
The reign of Ralpacan was characterized by conflicts with China and the Uyghur state to the North. Tibetans attacked Uyghur territory in 816 and were in turn attacked in 821. After troops were sent towards the Chinese border, Buddhists in both countries sought mediation and the Sino-Tibetan treaty completed in 821/822, which insured peace for more than two decades. Tibet also made peace with the Uyghurs and also, apparently, with Nanzhao in 822.
A bilingual account of the treaty with China, including details of the borders between the two countries is inscribed on a stone pillar, erected in 823, which stands outside the Jokhang temple in Lhasa. There was also a pillar with the treaty inscribed on it erected in China and a third was apparently placed at Gugu Meru at the border (which is said by locals to have been stolen by a party of French Tibetologists).
Culture and Buddhism 
He was a generous supporter of Buddhism and invited many craftsmen, scholars and translators to Tibet from China, Nepal, Kashmir and Khotan. He also promoted the development of Tibetan literature and translations, which were greatly aided by the development of a detailed Sanskrit-Tibetan lexicon called the Mahavyutpatti which included standard Tibetan equivalents for thousands of Sanskrit terms. He decreed that all translations must be done directly from Sanskrit.
Ralpachan built a magnificent nine-storeyed temple of 'U-shang-rdo near the confluence of the Tsangpo and Kyi rivers. The lower stories were of stone, the three middle ones of brick and the top three of wood. It was famous for its remarkable golden roof. On the top floors he stored Buddhist scriptures, chortens and images, while the middle floors were used by scholars and translators, and the bottom floors by the court and for state affairs. He also remodeled and restored older temples.
He introduced standard weights and measures based on the ones in China. He enforced the Indian canonical regulations for the clergy and organised many classes of priesthood, assigning a revenue from seven families for each Buddhist monk and proscribed strict penalties for anyone showing disrespect to them.
His royal summer camp near modern Lhasa was "a palatial military pavilion", "wonderfully decorated with golden figures of tigers, panthers, and dragons."
Death and succession 
Ralpacan was, according to the most common Tibetan tradition, murdered by two pro-Bon ministers who then placed his anti-Buddhist brother, Langdarma, on the throne. Some accounts suggest that his death was an accident due to a slip on the steps of the temple of Maldro, while the Later Tang Annals state that he became sick and was unable to take control of affairs of state and then, later, died.
The latter theory finds support in a damaged manuscript from Dunhuang containing a prayer for the good health of the king. The late Chinese work, the Tongjiangangmu by Zhu Xi (1130–1200), claims that Ralpacan had been sick for almost the whole of his reign and had, therefore, been unable to travel around his empire. He is said to have died at the end of the year 838.
Interestingly, this same work mentions under the very next year, 839, that a feverish epidemic had gone on for several years among the Uighurs killing "an infinite number of people." 
A reference to this epidemic in 839 is also found in the Xin Tangshu 217B.1b. It is possible that it was this epidemic which brought about Ralpacan's death, though it could equally have been the result of his chronic illness.
- dBa' bzhed: The Royal Narrative Concerning the Bringing of the Buddha's Doctrine to Tibet, p. 90. Translation and Facsimile Edition of the Tibetan Text by Pasang Wangdu and Hildegard Diemberger. Verlag der Österreichischen Akademie der Wissenschafen, Wien 2000. ISBN 3-7001-2956-4.
- Vitali, Roberto (1990) Early Temples of Central Tibet, p. 17. Serindia Publications. London. ISBN 0-906026-25-3.
- Stein, R. A. (1972) Tibetan Civilization, p. 63. Stanford University Press. ISBN 0-8047-0806-1 (cloth); ISBN 0-8047-0901-7 (pbk)
- Kolmaš, Josef. Tibet and Imperial China: A Survey of Sino-Tibetan Relations up to the end of the Manchu Dynasty in 1912 (1967), p. 8. Centre of Oriental Sudies, Australian National University, Canberra.
- Beckwith, Christopher I. The Tibetan Empire in Central Asia. (1987), pp. 165-167. Princeton University Press. ISBN 0-691-02469-3.
- Lee, Don Y. The History of Early Relations between China and Tibet: From Chiu t'ang-shu, a documentary survey, p. 150. (1981). Eastern Press, Bloomington, Indiana. ISBN 0-939758-00-8.
- Vitali, Roberto (1990) Early Temples of Central Tibet, p. 18. Serindia Publications. London. ISBN 0-906026-25-3.
- Beckwith, Christopher I. The Tibetan Empire in Central Asia. (1987), pp. 150-151. Princeton University Press. ISBN 0-691-02469-3.
- A Corpus of Early Tibetan Inscriptions. H. E. Richardson. Royal Asiatic Society (1985), pp. 106-143. ISBN 0-94759300/4.
- Shakabpa, Tsepon W. D. (1967). Tibet: A Political History, pp. 49-50. Yale University Press, New Haven & London.
- Ancient Tibet: Research Materials from the Yeshe De Project (1986), pp. 296-297. Dharma Publishing, California. ISBN 0-89800-146-3.
- Yoshinori Takeuchi, Jan van Bragt. Buddhist Spirituality. Crossroad, 1993. p. 225.
- Tantric Glossary
- Dás, Sarat Chandra. Contributions on the Religion and History of Tibet, p. 40. Manjushri Publishing House, Delhi (1970). First published in The Journal of the Asiatic Society of Bengal, Vol. L (1881)
- Ancient Tibet: Research Materials from the Yeshe De Project (1986), p. 296. Dharma Publishing, California. ISBN 0-89800-146-3.
- Shakabpa, Tsepon W. D. (1967). Tibet: A Political History, p. 51. Yale University Press, New Haven & London.
- Pelliot, Paul. Histoire Ancienne du Tibet. Paris. Libraire d'amérique et d'orient. 1961, p. 133.
- Richardson, H. E. "Khri Gtsug-lde-brtsan's Illness." Bulletin of the School of Oriental and African Studies, 44 (1981), p. 351-352.
- Grosier, Jean-Baptiste. Histoire Général de la Chine ou Annales de cet empire: traduites du Tong-kien-kang-mu. (1778) Paris. Reprint: Ch'en-wen publishing company, Taipei, Taiwan. 1969. XIII, p. 471.
- Grosier, Jean-Baptiste. Histoire Général de la Chine ou Annales de cet empire: traduites du Tong-kien-kang-mu. (1778) Paris. Reprint: Ch'en-wen publishing company, Taipei, Taiwan. 1969. XIII, p. 472.
- Mackerras, Colin. The Uighur Empire According to the T'ang Dynastic Histories: A Study in Sino-Uighur Relations 744-840, p 125. University of South Carolina Press, Columbia, South Carolina. 1972. ISBN 0-87249-279-6.
- Ancient Tibet: Research Materials from the Yeshe De Project (1986), p. 304. Dharma Publishing, California. ISBN 0-89800-146-3.