Birka's warrior was female in the 1970s. Nobody accepted it until 2017.

In 1878, the Swedish archaeologist Hjalmar Stolpe dug up a chamber grave on the island of Bjorko. The island was the site of Birka, a Viking-age trading town. He gave the grave the number Bj 581. It is one of the richest warrior burials ever found in Scandinavia.

The grave held a sword, an axe, a fighting knife and two spears. Two shields stood against the walls at the head and the foot. There was a quiver of twenty five armour-piercing arrows, and there were two horses, one with a bridle.

A bag lay in the lap of the body. It held twenty eight gaming pieces, three antler dice and a king piece marked with an iron nail. An iron-framed gaming board stood next to it.

The grave was on a raised terrace, directly next to the garrison and the hillfort. For a hundred and forty years, nobody had any doubt about it. This was a high-ranking professional warrior. Because of the gaming set, it was probably a commander. The osteologist Anna Kjellstrom said later, "Only a few warriors are buried with gaming pieces, and they signal strategic thinking."

The person in the grave was a woman.

Forty years of not listening

In the 1970s, an osteological analysis first found that the skeleton was female. People ignored the result.

In 2016, Anna Kjellstrom of Stockholm University examined the bones again. She got the same result again: female. She used the pelvis, the mandible and the standard skeletal markers.

In 2017, Charlotte Hedenstierna-Jonson of Uppsala University led a team that published a genomic study in the American Journal of Physical Anthropology. There was no Y chromosome, and there were two X chromosomes. That closed the question.

So the bones said the same thing for about four decades. The field listened only after the DNA result.

The objection that showed the real problem

After the 2017 paper, scholars made a serious argument against it. They said that the old interpretation of the grave could no longer stand. Grave goods do not prove a job. Weapons in a burial can be inherited wealth or a family display. They do not always show what the dead person did.

In theory, that objection is correct. The problem is the time when it came.

Since it was excavated in the 1870s, it has constantly been interpreted as a warrior grave because it looks like a warrior grave and it's placed by the garrison and by the hillfort. Nobody's ever contested it until the skeleton proved to be female, and then it was not a valid interpretation anymore.

Those are the words of Hedenstierna-Jonson. I think they are the clearest statement of the whole problem. Between 2016 and 2017, no evidence about the grave changed. The sword, the arrows and the gaming set were the same. Only the sex of the body changed. At that exact moment, the standard of proof went up.

The next argument was that these were the wrong bones. Maybe the museum mixed them up in storage over a century. That is a reasonable worry. But a small, wonderful detail defeats it. Stolpe was a very careful excavator. When he dug the grave, he wrote "Bj 581" on every single bone in India ink.

To be fair to the critics, some of the doubt is older than all of this, and it is not about sex. In 1980, Anne-Sofie Graslund argued that the name "warrior grave" says too much about any Birka grave. A pile of weapons can show a social elite, not a working soldier.

Judith Jesch criticised the 2017 paper for its use of written sources. She also said it did not consider other readings. The authors published a full response in Antiquity in 2019, and they did not change their position.

Those are real arguments. But nobody pushed them this hard against Bj 581 while everyone thought it held a man.

The princess who became a priest

Birka is the best documented case. The grave at Vix in Burgundy is the most extraordinary.

Rene Joffroy excavated it in 1953. It held a Celtic burial of enormous wealth: a solid gold torc, a four-wheeled wagon and a Greek bronze krater. The krater came from abroad and is more than a metre and a half tall. It is the largest metal vessel that survives from the ancient world. At that time, experts identified the body as female.

A woman with that much power was a difficulty for some scholars. In a 1983 book, the archaeologist Konrad Spindler gave his solution. He proposed that the body was not a woman with authority. It was a man in women's clothing: a transvestite priest.

For him, a third gender category was easier to accept than a female ruler.

The archaeologist Bettina Arnold destroyed this idea at a 1989 conference. She also wrote a paper, and its title says it all: "The Deposed Princess of Vix". Her point was about the whole discipline, not Spindler alone. It had a habit of removing powerful women from the past. The people with this habit could not see it, because it felt like caution to them.

Why this kept happening

Under both cases is a circular method. For a long time, this method was standard practice.

It is hard to find the sex of a skeleton, especially a broken one. Grave goods are easy to read. So excavators started to find the sex of the body from the objects in the grave. Weapons meant a man. Jewellery and spindle whorls meant a woman.

They applied the rule and put the results in tables. Then the tables proved that men had weapons in their graves and women had jewellery.

The method is completely circular. It assumed the conclusion at the time of measurement. Then it found that conclusion in the data and called it a discovery. That process could never find a female warrior, however many were in the ground.

Peru, and a really new kind of evidence

In 2018, excavators worked at a site called Wilamaya Patjxa, high on the Andean altiplano in Peru. They found a burial from between 9,000 and 8,700 years ago. The person was a young adult. Next to her was a toolkit for big-game hunting: projectile points and tools to butcher animals and process hides. Later, Aymara community members gave her a name, Warawara, which means star.

A proteomic analysis of her tooth enamel showed that she was female. That method is important. It does not depend on a quick look at a pelvis, or on the objects next to her.

Randall Haas and colleagues published the find in Science Advances in 2020. Then they looked for similar burials. They searched published records of late Pleistocene and early Holocene burials across the Americas: 429 individuals from 107 sites. They found 27 buried with big-game hunting tools. Eleven were female and fifteen were male.

From this, they estimated that between 30 and 50 per cent of big-game hunters in these populations were women.

The problem with the larger survey

Here I must be fair to both sides. The correction has its own problem, and it is the same problem.

Robert Kelly of the University of Wyoming accepts the Peruvian burial itself. But he showed the clear difficulty with the larger survey. Tools in a grave do not prove that the dead person used them in life. They can be offerings. They can be gifts from the living. And in Haas's sample of female "hunters", two were infants.

An infant with a spear point in the grave is not evidence of an infant hunter. It is evidence that somebody put a spear point in a baby's grave.

The old error read identity from grave goods: weapons, so male. Part of the new reading does the same thing in the opposite direction: weapons, so hunter. It is the same logic. It is not more correct because we like its conclusion.

The same pattern occurred in the ethnographic literature. In 2023, a paper in PLOS ONE had the title "The Myth of Man the Hunter". It said that women hunted in 79 per cent of the foraging societies it examined, fifty out of sixty three. In one week, the story went around the world.

In 2024, Vivek Venkataraman and colleagues checked the data. Nobody could reproduce the analysis. The sampling criteria were not clear. 35 per cent of the societies in the sample did not come from the database that the authors named. The coding had many errors.

Venkataraman's team coded the same societies again. In about a third of the cases that the original paper counted as women who hunt, women rarely or never hunted. PLOS ONE published a correction.

Their own conclusion is the honest one, and it is in their title: female foragers sometimes hunt, and gendered divisions of labour are still real.

What the record really supports

Nobody has counted the times that archaeologists refused to accept a female skeleton. If somebody gives you a number, they made it up. But we do have a documented pattern, with names and dates. In at least two cases, the refusal is beyond argument.

In Sweden, the bones identified a woman in the 1970s. She waited forty years and a genome before anyone acted on it. In France, scholars made a woman into a man in a dress, so that she did not have to be the person in charge.

This record does not show that women secretly did all the hunting and fighting. It shows something narrower and more damning. For a long time, the discipline let its assumptions do the work of its evidence. It did not notice, because the answers always agreed with what everyone expected.

Here is the lesson. When a piece of evidence gives an answer that you did not expect, you quickly learn the truth about your standard of proof. Was it ever about the evidence? Birka failed that test for forty years. The temptation now is to fail it in the other direction and call that progress.