They partied like it was 1999 … BC.

People were enjoying libations with coworkers long before the modern-day office soiree. Danish researchers potentially discovered the world’s oldest beer tab inscribed on a four-millenia-old clay tablet, as well as texts concerning anti-witchcraft rituals and ancient rulers, per a study entitled Hidden Treasures: The National Museum’s Cuneiform Collection.

The researchers, who hailed from the National Museum of Denmark and the University of Copenhagen, had discovered the ancient brew receipts while investigating the museum’s extensive collection of inscribed tablets from the earliest civilizations of the Middle East, Phys.org reported.

Many of them dated back thousands of years and were etched in cuneiform and other languages that have long been extinct.

For the first time ever, the researchers deciphered these cryptic glyphs, finding, among other things, a 4,000-year-old record of beer that was used as payment in the ancient city of Umma, in what is now Southern Iraq, the Daily Mail reported.

“There are several texts at the National Museum of Denmark included in our volume that mention beer being used as payment to workers,” Dr. Troels Arbøll, from the University of Copenhagen, told the publication. “They are, therefore, administrative documents or receipts.”

Supplied by a man named “Ayalli,” the haul of giggle juice comprised 16 liters of “high-quality beer” and 55 liters of “ordinary beer.”

These party favors were reportedly slated to be divided among a coalition of workers, potentially for the ancient equivalent of a booze-fueled office bash.

This find might seem anachronistic, but Arbøll pointed out that beer “was presumably high in nutrition and considered an integral part of how these earliest urbanized populations lived.”

Tate Paulette, an assistant history professor at North Carolina State University, wrote that beer was ubiquitous throughout Mesopotamia– the historical region that encompasses modern-day Iraq and Syria.

“Beer was the beverage of choice in Mesopotamia,” he wrote in a piece for The Conversation. “In fact, to be a Mesopotamian was to drink beer.”

Unlike a modern-day IPA or Pilsener, however, this ye olde suds wasn’t fermented from hops, but rather brewed using fermented bread or honey and dates.

Consumed via sipping through a straw, this age-old lager was milky and porridge-like and tasted sour and tangy with notes of wet clay. This rough “draft” was also much less boozy than its modern-day counterpart, clocking in at 3.5 to 6.5 percent alcohol.

Ancient Mesopotamian civilizations had been recording transactions and other important info on stone tablets as early as 5,200 years ago, helping accelerate their advancement by paving the way for advanced bureaucracy.

“There was a need to keep track of the advanced societies that were being built, and we have found a large number of cuneiform tablets containing practical information, such as accounts and lists of goods and personnel,” said Dr. Arbøl, per Phys.org. “It is therefore not surprising that one of the tablets in the National Museum’s collection contains something as commonplace as a very old receipt for beer.”

But beer bills weren’t the only stone docs found in the aforementioned treasure trove. Arbøll noted another tablet, found in the Syrian City of Hama that contained a “so-called anti-witchcraft ritual” that took an entire night and involved burning various wax and clay figurines while an exorcist recited incantations.

This custom was of “enormous importance to the royal authority in Assyria because it had the remarkable ability to ward off misfortunes—such as political instability—that might befall a king,” the researcher declared.

Other docs in the collection included a list of both real-life and mythical kings, including one that suggested that Gilgamesh was an actual historical figure.