After Trisong Detsan assumed the throne, Tibet became extremely prosperous. This Tibetan king advocated martial arts, not only occupying the four towns of Anxi on the Silk Road for long time, but also attacking Chang'an, the capital of Tang Dynasty, during the An Shi rebellion. This is recorded in the historical books of the Tang Dynasty. The Tibetan Historical Documents From Dunhuang also describes how "the Tibetan General Chata Lokang led a powerful force to the capital and occupied it. After the Tang emperor escaped, a new emperor was enthroned. Then the force retired." There is an obelisk in Lhasa with the carved inscription recording the military successes of Chata Lokang. It still stands at the northeastern corner of the square of the Potala Palace.

During the period from 775 to 787, Trisong Detsan invited Master Padmasambhava from India to Tibet to promote Buddhism. He presided over the construction of the Samye Monastery complete with Buddha statues and resident monks (1978)