Famensi is one of China's oldest Buddhist foundations, traditionally said to have been established under the Eastern Han dynasty to house a relic of the Buddha, though its documented importance begins under the Tang, when a succession of emperors had the temple's relic ceremonially escorted to the capital Chang'an and back, roughly once a generation between the seventh and ninth centuries. The last of these imperial processions, in 873, ended with the relic and a great quantity of accompanying treasure sealed into an underground crypt beneath the pagoda the following year, apparently as a devotional act rather than for safekeeping alone, and the crypt was then effectively forgotten for over a millennium.
The temple's Ming-dynasty pagoda, built centuries later on the same site, partially collapsed in 1981, and repair work in 1987 broke through into the sealed Tang crypt, still closed exactly as the 874 dedication had left it. Excavators found not one but four bone objects presented as Buddha relics, along with a documented stone inventory naming the treasures buried with them; three of the four are understood as replica or substitute relics of a kind Tang Buddhist practice used precisely to protect the genuine object from theft or loss, a strategy the crypt's own inscriptions describe. The museum was built to display this find in place, making Famensi one of the few sites where an intact, dated, imperially documented Buddhist deposit can be seen essentially as it was buried.