These undeciphered symbols date back to Roman times | Science

What’s in a name? For the ancient Picts—a federation of Celtic-speaking tribes that lived in modern-day Scotland—the answer might go something like “salmon-beast” or “fish-flower.” Those are just two combinations of some 30 mysterious symbols that this society of farmers, who lived between the third and 10th centuries C.E., carved into hundreds of freestanding stone monuments and bone tools. But the symbols have not been deciphered, and their meaning has perplexed researchers for centuries. Now, archaeologists may have gotten one step closer by figuring out when the earliest symbols appeared.

Because most Pictish symbols are carved in stone, they can’t be dated using traditional methods that rely on the decay rate of organic materials. Instead, archaeologists have relied on imprecise rules of thumb that suggest symbols incised on unshaped stones in this part of the world usually date to about the fifth century C.E. But that evidence is highly circumstantial and not considered as accurate as direct dating.

In the early 19th century, a group of children discovered carvings in a wall that belonged to Dunnicaer, a Pictish fort site on Scotland’s eastern coast. In recent archaeological excavations of the site, diggers also found traces of organic material—several slivers of preserved timber and a piece of charcoal in an ancient hearth. Scientists radiocarbon dated these objects, and more timber from a site farther inland, to about 200 C.E. to 300 C.E. They also dated an ox bone and a bone pin from a Pictish site on the Orkney Islands (pictured above) to about 400 C.E. Taken together, the findings suggest the Pictish symbols date to at least the early third century, they report today in Antiquity.

That means the symbols are nearly 200 years older than previously thought. The new time frame also lines up with the spread of Roman writing systems through the region, suggesting the Picts’ enemies may have partially inspired their script. Although the Picts didn’t adopt the Roman alphabet, they may have picked up the idea of using symbols to represent significant names and places, the authors argue. That makes sense, they say, given that at least some of the stone monuments appear to mark important sites—and their rulers.