Shattered pots and other artifacts have much to teach us about vanished civilizations, but, sometimes, it’s what’s inside that counts. Researchers have identified molecular traces of diseased human organs inside clay pots from the Iron Age. They describe their discovery in a forthcoming issue of The Journal of Archaeological Science.

DKrieger via Wikimedia Commons // CC BY-SA 3.0

The settlement at Heuneburg in modern-day Germany was part of one of the earliest cities ever built among the Alps. At the height of its success during the 6th century BCE, Heuneburg was home to more than 5000 people. Those people left behind stone walls and mud-brick buildings, fields and burial mounds.

Nestled within one of those burial mounds were six ceramic jars. By the time archaeologists reached them, the jars were smashed, and their contents had decomposed beyond recognition—at least to the naked eye.

A team of three archaeologists and one biochemist found a way to reconstruct what was once there. They took teeny samples from each pot, ground them up, and washed them in a chemical solution to collect any proteins that might remain. They then compared the 166 different compounds they’d found with a large protein database, looking for matches.

What they found was surprising, to say the least. Some of the proteins came from human blood. Others were from human organ tissue. Still others belonged to a virus called Crimean-Congo hemorrhagic fever (CCHF). This tick-borne disease starts with a sudden fever and headache, progresses to vomiting and nosebleeds, and can end in uncontrolled bleeding and death. It still kills people today across a wide region stretching from western Asia through southern Africa.

The presence of organ and blood proteins inside the jars suggests that the people of Heuneburg cared lovingly for their dead, interring each organ in its own fine receptacle.

The researchers aren’t sure what the virus’s appearance in Heuneburg might mean; we’ve never found hemorrhagic fever on ancient artifacts before.

Lead author Conner Wiktorowicz, of Purdue University, says his team’s methods and findings open new portals into the world of the dead.

"What have archaeologists been missing regarding social practices and the use of pottery vessels in the past?" he said in Science magazine. “I can’t imagine all of the exciting new findings other researchers will make."