(Tib., Srong-bstan sgam-po). One of the three great religious kings of Tibet. He was a formidable warrior and politician who unified much of Tibet into a single state and opened successful diplomatic relations with the T'ang Chinese and other countries. It was during his reign that Buddhism made its first tentative inroads into Tibet with the construction of the Jokhang. Noteworthy also is the introduction during his reign of a writing system based on a north Indian model.