c. 5000 BCE     Dried peyote buttons dating from this era are later found in Shumla Cave, Texas.

c. 4000 BCE     Opium poppies are cultivated in the Fertile Crescent (now Iran and Iraq) by the ancient cultures of Mesopotamia.

1552 BCE     An ancient Egyptian papyrus text from the city of Thebes lists 700 uses for opium.

c. 1300 BCE     A Peruvian carving depicting a San Pedro cactus, a source of mescaline, is made on stone tablets.

c. 700 BCE     Archaeological tablets record that Persians and Assyrians used cannabis as a drug.

c. 199     Galen (129–c. 199), a medical authority during late Antiquity and the Middle Ages, creates a philosophy of medicine, anatomy, and physiology that remains virtually unchallenged until the sixteenth and seventeenth centuries.

c. 200     Chinese surgeons boil hemp in wine to produce an anesthetic called ma fei san.

c. 400     Hemp is cultivated in Europe and in England.

600-900     Arabic traders introduce opium to China.

1000     In Coahuila...