Cannabis residues were found in incense burners . Apparently used in funeral rites at a mountain site in western China around 500 B.C. Providing what is perhaps the oldest evidence of the use of cannabis for its mind-altering properties. China: The oldest evidence of cannabis inhalation
Cannabis is one of the oldest plants in East Asia. It is grows for the manufacture of grains and fibers for recreational, medicinal and ritual purposes.
Archaeological evidence of the ritualistic use of cannabis is scant and controversial.
Here for instance , we present some of the first directly and scientifically verified evidence of the ritual of cannabis smoking.
Evidence indeed on 10 wooden braziers containing stones with burn marks discovered in 8 tombs in the Jirzankal Cemetery (about 500 B.C.) in the Pamir Mountains in the Xinjiang region of China, scientists announced.
The tombs also bore human skeletons and artifacts, including a type of angular harp used in ancient burials and sacrificial ceremonies.
China has at least 2,500 years of experience with ritual and/or religious activities in China and has produced high levels of psychoactive compounds.
You can find the scientific article by clicking on this link.