Entheogenic use of cannabis
Cannabis has served as an entheogen—a chemical substance used in religious or spiritual contexts—in the Indian subcontinent since the Vedic period dating back to approximately 1500 BCE, but perhaps as far back as 2500 BCE in Ancient China. It was introduced to the New World by the Spaniards in 1530-1545.
Source: Wikipedia — Entheogenic use of cannabis (CC BY-SA 4.0)