The skulls, found in 2011 at an excavation site in Motala, central Sweden, are understood to be from around 8,000 years ago.
At the time they were found, scientists were baffled as to why some of the skulls were mounted on wooden stakes. The unusual discovery was believed to be the first of its kind anywhere in the world, as The Local reported at the time.
This week, scientists have revealed more information about the bones of the nine adults and one newborn child.
"The majority of the skulls have traces of healing injuries in the same area on the head. It appears to be repetitive and there are differences between the men's and the women's injuries," Anna Kjellström of the Stockholm University said in a statement.
Writing in the journal Antiquity, Kjellström and her colleagues explained that the women had injuries on the back and the right side of their head, while the men had injuries at the top of their heads.
They said these injuries were caused by "interpersonal violence".
Researchers believe the people were important in some way – although it's near impossible to figure out why, not least because there have been no similar discoveries in Europe from the same time.
As to why the skulls were put on stakes, Kjellström still has no answer.
"It could have been an intimidation tactic to scare enemies, but it could very well have been for a different reason. In any case, it would have been a stunning and spectacular sight," she said.
The skulls were found at the Kanaljorden excavation site with the stakes inserted the full length from the base to the top of the skull.
In another case a temporal bone of one individual identified as a female was found placed inside the skull of another woman.
The bones were found in what was a shallow lake during the early Stone Age which appears to have served as a ceremonial burial site.
"Clearly this lake was some sort of holy place for the people who lived here at the time," archaeologist Fredrik Hallgren told The Local at the time of the discovery.
Another dig site nearby in Motala gained worldwide attention in 2010 when archaeologists uncovered what was believed to be a Stone Age dildo.
The object, which measured 10-11 centimetres (4 inches) long and 2 centimetres in diameter, had been fashioned from a stag's antler.