Tibetan Empire

The Tibetan Empire (Tibetan: བོད་ཆེན་པོ, Wylie: bod chen po, lit. 'Great Tibet') was centered on the Tibetan Plateau and formed as a result of expansions under the Yarlung dynasty's 33rd king, Songtsen Gampo, in the 7th century. It expanded further under Trisong Detsen and reached its greatest extent under Tritsuk Detsen, stretching east to Chang'an, west beyond modern Afghanistan, south into modern India and the Bay of Bengal. It is referred to as Tufan or Tubo (吐蕃) in Chinese sources.

The Yarlung dynasty was founded in 127 BC in the Yarlung Valley along the Yarlung River, south of Lhasa. The capital was moved in the 7th century from the Yungbulakang Palace to Lhasa by the 33rd ruler Songtsen Gampo, and into the Red Fort during the imperial period which continued to the 9th century. The beginning of the imperial period is marked in the reign of the 33rd king of the Yarlung dynasty, Songtsen Gampo. Tibet's military power gradually increased over a diverse terrain. During the reign of Trisong Detsen, the empire became more powerful and increased in size. At this time, a 783 treaty between the Tibetan Empire and the Tang dynasty defined the borders, as commemorated by the Shol Potala Pillar in Lhasa. Borders were again confirmed during the later reign of Tritsuk Detsen through his 821–823 treaty, which was inscribed on a pillar at Jokhang. In the opening years of the 9th century, the Tibetan Empire controlled territories extending from the Tarim Basin to the Himalayas and Bengal, and from the Pamirs into what are now the Chinese provinces of Sichuan, Gansu and Yunnan. The murder of Tritsuk Detsen in 838 by his brother Langdarma, and Langdarma's subsequent enthronement followed by his assassination in 842 marks the simultaneous beginning of the dissolution of the empire period.