Smithsonian.com

Pottery beakers were used to hold the “Black Drink”. Photo: L. Brian Stauffer / University of Illinois at Urbana-Champaign

Unearthed in Cahokia, a site near modern day St. Louis, Missouri, archaeologists found tea residue in pottery beakers that dates to as early as 1050 A.D.

The research, lead by Patricia Crown of the University of New Mexico, pushes back the date on when southeastern US civilizations started drinking tea by at least 500 years. Unlike the teas that were later imported to the region, “the highly caffeinated tea was brewed from the shrub Ilex vomitoria, a species of holly,” says Science. The tea, known as “Black Drink,” is thought to have held an important ritualistic or spiritual significance. The University of Illinois at Urbana-Champaign:

Different groups used the black drink for different purposes, but for many it was a key component of a purification ritual before battle or other important events. Its high caffeine content – as much as six times that of strong coffee, by some estimates – induced sweating. Rapid consumption of large quantities of the hot drink allowed men to vomit, an important part of the purification ritual.

What’s more, says Science, the discovery supports the idea that a vast, organized trading system existed at the time.

[B]ecause the bushes weren’t native to Cahokia but to the coastal region between eastern Texas and Florida, the leaves must have been brought to the inland city through trade routes connecting the two areas, which suggests the drink had huge cultural importance.

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