Testament of Ba in the context of Songsten Gampo

The Yarlung dynasty (Tibetan: བོད་ཀྱི་གདོད་མའི་མངའ་མཛད།) was a Tibetan dynasty that existed from 127 BCE to 842 CE. It produced 42 rulers and gave rise to the Tibetan Empire period from 614 CE to 848 CE, credited to the 33rd monarch Songtsen Gampo, and lasting through to the 40th monarch Ralpachen. Ralpachen was murdered in 838 by his brother, the future 41st monarch Ü Dum Tsen, who in turn ruled for only one year (841–842) until his own murder. The dissolution of the empire occurred by 848.

The early Yarlung dynasty rulers lived before the Tibetan script was created, and their reigns and lives were documented through the lineage of verbal history until c. 650 when in the reign of the 33rd king of the Yarlung Dynasty Songtsen Gampo, the Tibetan alphabet and grammar were created and the royal record keeping of people and events called the Chronicle of Ba began. While some scholars feel unsure of the definitive existence due to the lack of written records before 650, the verbal lineage of Tibetan history is considered definitive for most scholars.

Tritsuk Detsen (Tibetan: ཁྲི་གཙུག་ལྡེ་བཙན, Wylie: khri gtsug lde btshan), better known by his nickname Ralpachen (Tibetan: རལ་པ་ཅན, Wylie: ral pa chen) (c. 802 CE–838), was the 40th king of the Yarlung Dynasty of Tibet. He reigned after the death of his father, Sadnalegs, in c. 815, and grew the empire to its largest extent. He was murdered by his younger brother Langdarma in 838. Ralpachen is one of Tibet's three Dharma Kings, and referred to as "son of God" in the ancient Tibetan chronicle Testament of Ba.

Ralpachen was the second eldest of five brothers. The eldest, Prince Tsangma, took Tibetan Buddhist vows with the Nyingma school. The third, U Dumtsen known as Langdarma,is referred to in the sources as "unfit to reign". The younger two brothers both died young.

Padmasambhava ('Born from a Lotus'), also known as Guru Rinpoche ('Precious Guru'), was a semi-legendary tantric Buddhist Vajra master from medieval India, who according to hagiographical sources fully revealed the Vajrayana in Tibet, circa 8th – 9th centuries. He is considered an emanation or Nirmāṇakāya of Shakyamuni Buddha as foretold by the Buddha himself. According to early Tibetan sources including the Testament of Ba, he came to Tibet in the 8th century and designed Samye Monastery, the first Buddhist monastery in Tibet during the reign of King Trisong Detsen. He, the king, and Khenpo Shantarakshita are also responsible for creating the Tibetan Canon through translating all of the Buddha's teachings and their commentaries into the Tibetan language.

According to Lewis Doney, while his historical authenticity was questioned by earlier Tibetologists, it is now "cautiously accepted.” Padmasambhava himself was recorded as saying he was a historical person, and his footprints left in rocks are evidence. Padmasambhava later came to be viewed as a central figure in the transmission of Buddhism to Tibet. Starting from around the 12th century, hagiographies concerning Padmasambhava were written. These works expanded the profile and activities of Padmasambhava, now seen as taming all the Tibetan spirits and gods, and concealing various secret texts (terma) for future tertöns. Nyangral Nyima Özer (1124–1192) was the author of the Zangling-ma (Jeweled Rosary), the earliest biography of Padmasambhava. He has been called "one of the main architects of the Padmasambhava mythos – who first linked Padmasambhava to the Great Perfection in a high-profile manner."