Details will appear in a forthcoming issue of the Danish Journal of Archaeology. But if your curiosity is more immediate and tends toward the gustatory, head to a nearby wine-and-beer store and request a bottle of the most recent Ancient Ale from Dogfish Head. The Delaware-based brewery launched its Ancient Ale Series in 1997, and in 1999 collaborated with McGovern to make Midas Touch, a brew that was inspired by the residue found on pottery fragments in a 2,700-year-old tomb in Turkey. Dogfish Head has since re-created six other defunct potables with McGovern, based on archeological finds in China, Honduras, Peru, Egypt, Italy, and now Scandinavia. Its re-creation of Nordic grog, Kvasir, is named after a mythical Norse hero who was born out of saliva and later killed by dwarfs. Dogfish Head made about 2,300 cases, available this winter in 27 states.

Dogfish Head’s Ancient Ales may vary in geography and taste, but they all have one thing in common: “Invariably, every one of these ancient beverages that we’ve brought back to life had at least two sources of sugar,” says the company’s founder and president, Sam Calagione, “be they honey or grapes or fruits or grains.”

One might wonder why early societies would use such a mash-up of flavors. But the more vexing question is: Why did they stop? Why did complex, deeply layered beverages get siloed into restrictive categories—mead from honey, wine from grapes, beer from grain—which then became increasingly homogenized over time? How did we get from Nordic grog to Bud Light?

Calagione heaps some of the blame on restrictions imposed by Bavarian rulers in 1516, which would later become known as the beer-purity law. “They mandated that beer could only be made with water, barley, and hops,” he says. “Humans had been brewing these exotic hybrid beers for 10,000 years, yet now roughly 99 percent of the beer commercially made around the world references a 500-year-old tradition. It’s a war the Germans have pretty much won.”

For his part, Penn’s McGovern sees a natural progression toward specialization, as beer makers started producing on a larger scale. “They get a successful product using a limited range of ingredients that people like and understand,” he says, “and then they flood the market with it.”

Kvasir is not what anyone would consider a streamlined product. It’s a hybrid of beer, fruit wine, and mead, flavored with (among other ingredients) yarrow, lingonberries, cranberries, bog myrtle, and birch syrup. “The ingredient I’m most excited about is the lingonberries,” Calagione says. I had thought Kvasir would have a boggy, primeval flavor, but instead it tasted quite modern: bright and tart, with an extremely dry finish.

Calagione won’t discuss Dogfish Head’s next Ancient Ale, other than to say, “It won’t even be defined as a beer. It’s even more experimental.”

But it’s safe to say it will be old. Very, very old.