(CN) – A study published Thursday found that the unusually persistent reign of the South American empire immediately preceding the Inca is attributable to one major factor — a steady supply of beer.

A thousand years ago, the Wari Empire stretched across modern day Perus, controlling land the approximate size of the United States’ eastern seaboard for 500 years.

Lasting from 600 to 1100 A.D., the Wari Empire remnants haven’t the same grandeur as the Inca ruins, which include Machu Picchu, but archeologists are gaining new insight into how the culture maintained its hegemony for half a millennium.

“This study helps us understand how beer fed the creation of complex political organizations,” said author Ryan Williams, an anthropologist with the Field Museum of Natural History in Chicago. “We were able to apply new technologies to capture information about how ancient beer was produced and what it meant to societies in the past.”

Approximately 20 years ago, Williams, his colleague Donna Nash and other members of the team were exploring archaeological artifacts in the mountains of southern Peru when they discovered what they believed to be an ancient brewery dating back to the Wari Empire.

“It was like a microbrewery in some respects,” Williams said. “It was a production house, but the brewhouses and taverns would have been right next door.”

The discovery prompted Williams and his team to further explore the role beer played in the complex social arrangements of the ancient empire.

The Wari brewed a beer they called chicha that was light in color with a distinctly sour taste. Because the beverage was only good for about a week after it was brewed, it was never shipped off-site.

Instead, travelers from all over the empire voyaged to festivals at Cerro Baúl to imbibe and carouse.

The festivals weren’t simply a place to blow off steam and celebrate, as they were attended by political elites who drank chicha out of highly decorated three-foot-tall vessels with images of Wari gods.

“People would have come into this site, in these festive moments, in order to recreate and reaffirm their affiliation with these Wari lords and maybe bring tribute and pledge loyalty to the Wari state,” Williams said.

Beer and the accompanying ceremonies were an instrumental part in keeping the Wari Empire together, according to the study.

The researchers were not content with a superficial examination of the archeological site and the remnants of the ceramic vessels. Instead, they employed lasers to break down the vessels to the molecular level, understanding from where the ceramic materials derived and how the beer was made.

“The cool thing about this study is that we’re getting down to the atomic level,” Williams said. “We’re counting atoms in the pores of the ceramics or trying to reconstruct and count the masses of molecules that were in the original drink from a thousand years ago that got embedded into the empty spaces between grains of clay in the ceramic vessels.”

The analysis yielded insight into the ingredients of the beer — which was fermented from pepper berries — and the ceramic materials were all local. Pepper berries were an important source for the drink because of their drought resistant nature, ensuring there was a steady supply of beer for the Wari.

Archeological techniques both new and old weren’t the only tools in play, as Williams and his team worked with modern brewers in Peru to recreate to confirm whether the ingredients comprising chicha could reliably be transferred to the vessels.

“Making chicha is a complicated process that requires experience and expertise,” said Nash, who along with curating at the Field Museum is a professor at University of North Carolina Greensboro. “The experiments taught us a lot about what making chicha would look like in the ruins of a building and how much labor and time went into the process.”

Williams and the other authors argue the beer was vital not only to Wari culture, but to its flourishing as an empire that grew and lasted for several centuries.

“We think these institutions of brewing and then serving the beer really formed a unity among these populations,” Williams said. “It kept people together.”