Сонгцэн Гампо
While some stories depict Buddhism in Tibet before this period, the religion was formally introduced during the Tibetan Empire (7th-9th century CE). Sanskrit Buddhist scriptures from India were first translated into Tibetan under the reign of the Tibetan king Songtsän Gampo (618-649 CE). This period also saw the development of the Tibetan writing system and classical Tibetan.