Archaeologists have discovered that people living 700 to 900 years ago in Cahokia, a massive pre-Columbian settlement near the confluence of the Missouri and Mississippi Rivers, ritually used a caffeinated brew made from the leaves of a holly tree that grew hundreds of miles away.
The discovery – made by analyzing plant residues in pottery beakers from Cahokia and its surroundings – is the earliest known use of this ‘black drink’ in North America. It pushes back the date by at least 500 years, and adds to the evidence that a broad cultural and trade network thrived in the Midwest and southeastern U.S. as early as 1050 CE.
The study, published in the Proceedings of the National Academy of Sciences, reveals the cultural importance of Greater Cahokia, a city with as many as 50,000 residents in its heyday, the largest prehistoric North American settlement north of Mexico.
Europeans were the first to record the use of what they called ‘the black drink’ by Native American men in the southeast. This drink, a dark tea made from the roasted leaves of the Yaupon holly, Ilex vomitoria, contains caffeine.
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.
At the same time the black drink was in use at Cahokia, a series of sophisticated figurines representing agricultural fertility, the underworld and life-renewal were carved from local pipestone. Most of these figures were associated with temple sites.
“We postulate that this new pattern of agricultural religious symbolism is tied to the rise of Cahokia – and now we have black drink to wash it down with,” said Dr Thomas Emerson, the director of the Illinois State Archaeological Survey and a collaborator on the study.
The beakers, too, appear to be a Cahokia invention. They look like single-serving, cylindrical pots with a handle on one side and a tiny lip on the other. Many are carved with symbols representing water and the underworld and are reminiscent of the whelk shells used in black drink ceremonies – recorded hundreds of years later – in the southeast, where the Yaupon holly grows.
“The researchers chose to look for evidence of black drink in the beakers because the pots were distinctive and fairly rare,” Dr Emerson said.
The team found key biochemical markers of the drink – theobromine, caffeine and ursolic acid – in the right proportions to each other in each of the eight beakers they tested. The beakers date from 1050 CE to 1250 and were collected at ritual sites in and around Cahokia.
Bibliographic information: Crown et al. 2012. Ritual Black Drink consumption at Cahokia. PNAS, published online before print August 6, 2012; doi: 10.1073/pnas.1208404109