Archaeologists have found two rare boat burials from the Viking age in Sweden, offering what they say is a glimpse into how customs and practices changed in the tumultuous era of raids, religious conversion and trade.
The burials were found in Gamla Uppsala, underneath a plot of modern houses near a parish, said a Swedish research firm, called the Archaeologists, that is part of the state-run National Historical Museums.
The researchers have yet to confirm the age of the graves, but believe they date to the 10th century. One of the burials had been damaged, likely when a cellar was built nearby, but the other was found intact, with the remains of a man in the stern of the boat.
A horse and a dog were buried in the bow of the boat, with a sword, spear, shield and ornate comb. The buried man was likely a very wealthy member of Viking-age society, said Johan Anund, the regional manager for the Archaeologists.
Mr. Anund said that part of what made the graves “exceptional” was that unlike other Viking-age burials in the area, neither the boats nor the remains were cremated — a traditional practice in the region for hundreds of years.
“Uncremated boat graves are extremely rare, and the chances to excavate them are even scarcer,” he said. Noting the historic significance of Gamla Uppsala, a center of religious and political power in the Viking age, Mr. Anund called the excavation a “once in a lifetime opportunity for an archaeologist.”
He suggested that the burials reflected the arrival of Christianity in Scandinavia, saying that though boat burials were “very pagan,” the decision to not cremate the grave was a “radical new” element influenced by Christianity.
It was not unusual for Viking-age people to be buried with animals, Mr. Anund said, “but the massive statement in the boat graves — with unburnt horses, dogs, big birds like falcons, pigs, sheep and bear pelts — is something else.”
He said the offering was a sign of status to the living and “a message to the ‘other side’ about who was coming there.”
Mr. Anund said boat burials were often for “petty kings” or chieftains who ruled over smaller regions — not quite rulers of kingdoms, but some of their families probably became members of the nobility “in the medieval sense” later on.
The site was being excavated because the parish intends to build a new hall there, and the graves were originally found in November. But the archaeologists delayed any announcement until early July, when the dig was almost finished, for fear that publicity would draw the attention of grave robbers.
Although ship burials are relatively rare in Sweden, they have been found across other parts of Northern Europe, said Dr. Elizabeth Ashman Rowe, who teaches Viking history at the University of Cambridge and was not involved in the research.
She said that ships and boats were common in Viking funerary rites, but Viking-age burial practices could be remarkably distinct from one region to another. At one site north of Uppsala, she said, men were found interred in boats and women were cremated; at another site, the women were buried in boats, the men cremated.
Dr. Rowe suggested that the mix of practices seen at the newly found boat burials could reflect the movement of Viking-age people: aristocratic visitors from the north, perhaps, or travelers on the trade routes between Denmark and Sweden.
“My guess about this ship burial is that it’s later than the large or extremely large burial mounds at Uppsala,” she said. “Fashions, as it were, had changed.”
She added that Viking-age people also used boats in cremations, though not in the way that popular culture often depicts it, with a fiery arrow shot into a longboat laden with kindling.
“These cremations were held on land,” she said, “and were not a floating ship set afire.”