Chemical tests of ancient pottery jars reveal that beer was produced about 3,500 BCE in what is today Iran, and was one of the first-known biological engineering tasks where the biological process of fermentation is used; the earliest chemically confirmed barley beer to date was discovered at Godin Tepe in the central Zagros Mountains of Iran, where fragments of a jug, from between 5,400 and 5,000 years ago was found to be coated with beerstone, a by-product of the brewing process.

Evidence of early beer brewing has been confirmed by finds at the Sumerian settlement of Godin Tepe in modern-day Iran going back to between 3500-3100 BCE but intoxicants had already become an integral aspect of daily human life long before.