In 2017, road workers in Perth, Scotland, stumbled upon a hulking stone lying about three feet belowground. Etched with the outline of a human figure carrying a spear, the ancient carving was faint, leading experts to use high-tech methods like 3-D imaging and photogrammetry to recreate it. Now, writing in the journal Antiquity, researchers have revealed new details about the mysterious figure—including, among other things, his “pronounced” buttocks and “robust” torso.

Known as the “Tulloch Stone” in a nod to the area where it was found, the monolith dates to the first millennium A.D., when northern and eastern Scotland were occupied by the Picts, a confederation of tribes perhaps best known for their bitter conflicts with the Romans. The Picts left behind hundreds of still-mysterious monumental stones engraved with depictions of humans and animals, as well as abstract and geometric symbols.

In the case of the Tulloch Stone, the figure depicted is clearly a warrior. His spear boasts a kite-shaped blade and what the study’s authors deem a “doorknob-style butt.” The shape of his head is crested, which the study says “probably indicates an elaborate hairstyle rather than a helmet or other headgear.” Lines across the warrior’s ankles may indicate that he was once shown with footwear or “tight leggings.”

The researchers suggest that the stone once stood near an ancient ring-ditch believed to mark a burial ground but was displaced when a soccer stadium was built in the area in the 1980s.

The Tulloch Stone is particularly significant when viewed in conjunction with two similar Pictish stones found at Rhynie in Aberdeenshire and Newton of Collessie in Fife. These slabs depict warriors armed with “doorknob-style” spears and, like the Tulloch Stone, were discovered near burial grounds. The warriors featured in the carvings could represent specific individuals buried in the cemeteries, but given that the figures appear to be standardized, a more likely explanation is that they depict “a generic sacred image,” says Mark Hall, archaeological curator at the Perth Museum and first author of the new paper, in a University of Aberdeen statement. Perhaps, the study authors write, the warriors reflect “a martial ethos embodied and legitimi[z]ed by invoking a mythical hero, ancestral figure or god.”

Martial imagery from this period in northern Britain is relatively rare—somewhat surprisingly, given what we know about the history of the Picts. These ancient people engaged in nearly continuous warfare with the Romans as they expanded their reach into Scotland. Study author Gordon Noble, a professor in the school of geosciences at the University of Aberdeen in the United Kingdom, tells Live Science’s Yasemin Saplakoglu that the warrior lifestyle, though initially adopted in the fight against the Romans, would have inevitably become a key part of Pictish culture.

Archaeological evidence unearthed in England testifies to what the study describes as a “warrior ethos” shared by the historic groups who lived there. Plenty of early Anglo-Saxon burials were furnished with weapons, and one need look no further than the epic poem Beowulf to understand the importance of warrior culture during this period. But this culture “has not been evidenced in Scotland in the same way,” according to Hall.

The Tulloch Stone, along with the two other monoliths depicting similarly war-like figures, thus help bridge “a crucial gap in knowledge,” says Noble in the statement. The carvings were probably associated with important cemeteries that belonged to elite groups, the study notes—a sign that a “war-oriented social organization” may have played a key role in fueling the hierarchical societies that took hold in Scotland during the post-Roman period. Further discoveries, the study’s authors hope, will only deepen our understanding of Scotland’s early inhabitants.

“It is likely that there are more Pictish stones out there to be found,” notes Hall, “and every new stone is a fantastic addition to the corpus.”