[4] An enormous number of early manuscripts in a variety of languages were collected by A. Stein and P. Pelliot at the famous sealed-up Library Cave (no.
From the time the Chinese Princess Wencheng arrived in 643 CE until Songtsen Gampo's death in 650 it is possible to accurately date the entries.
For example, in 763 CE, Tibetan soldiers captured the Chinese capital of Chang'an for fifteen days when the ruling Tang dynasty was recovering from the An Lushan Rebellion.
[9] These accounts, generally accepted as sober court records, provide a priceless view of Tibet in its early phase of expansion and establishment as a powerful empire.
They also provide a valuable way of checking and dating events mentioned in later Tibetan and Chinese historical records.