Their reputation is one of rampaging violence, brutality, rape and pillaging.

But while debate has raged for generations over whether the Vikings were really as bad as they’ve been portrayed, it now seems that when it came to human sacrifices, they did have at least a bit of a ruthless side.

And, according to one new theory surrounding the Vikings’ arrival in the Christian stronghold of Whithorn more than 900 years ago, the Norsemen – typically depicted with flowing hair, long beards and brandishing terrifying weapons – were, indeed, prone to despatching a human or two in the hope of appeasing their gods.

The new theory that human sacrifice did take place at the Dumfries and Galloway site has emerged as a raft of new understanding about the Vikings’ presence in the area is being unravelled through work carried out on the Galloway hoard.

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The dazzling collection of around 100 pieces of silver, gold, jewels, textiles, glass and earthern objects from the Viking Age was found in Kirkcudbrightshire in 2014, and is regarded as one of the most significant discoveries ever found in Scotland.

The Herald: A collection of around 100 pieces of silver, gold, jewels, textiles, glass and earthern objects from the Viking Age was found in Kirkcudbrightshire in 2014A collection of around 100 pieces of silver, gold, jewels, textiles, glass and earthern objects from the Viking Age was found in Kirkcudbrightshire in 2014 (Image: PA)

Its treasures, including silver from a church and runic inscriptions found to be Anglo Saxon inscriptions, not Norse, are helping to build up new ideas of how the Vikings interacted, traded and mingled with local people.

Further new understanding is being unpicked by a forensic examination of burial remains excavated from the site more than 20 years ago.

The notion of human sacrifice at the Whithorn site has been explored by Dr Shane McLeod, Post-Doctoral Research Associate, Institute for Northern Studies at University Highlands and Islands in Perth. He will present a talk on his theories at the town’s Soutar Theatre, AK Bell Library, on Monday, May 15.

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He said he had come to the conclusion that Vikings had carried out human sacrifice at the site, part of the Anglo-Saxon kingdom of Northumbria at the time and one of four major Bishops’ seats, after studying details from the previous excavations.

Among the many burial sites uncovered at the time was one particular group which seemed to be at odds for a Christian monastery.

The Herald: Vikings arrived in the Christian stronghold of Whithorn more than 900 years agoVikings arrived in the Christian stronghold of Whithorn more than 900 years ago (Image: Getty)

“There was a child buried with an amber necklace, which is quite common in the Viking age -  Christian burials not usually have necklaces or any goods,” he said.

“Next to it was a bundle of bones, including part of adult female and part of adult male, neither were complete.

“They died quite a long time previously and were possibly dug up and reburied, wrapped up in a bag, and laid next to the child.

“The female skull was placed inside the male skull. The other unusual thing was the burial site included the forelimb of a cow. It’s uncertain whether that’s by mistake but finding animal bones in Viking burials is quite common.

“What is interesting is that above this is spread a layer around 2kg of cremated bone that includes at least four humans - not animals.”

Dr McLeod said it appears that cremation had been used by the Vikings at the time to dispose of bodies. “Christians were not cremating themselves at this time in history, so it has to be a Viking site – they are the only ones in Britain at the time using cremation,” he adds.

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The cremation layer is similar to other sites in Eastern Europe, where cremated animal remains are spread over a burial site as a sacrifice offering. Having studied other locations, Dr McLeod had come to the conclusion that the site at Whithorn also contain sacrificed remains.

“But instead of animals, it appears to be human remains.”

That, he adds, raises the possibility that Vikings carried out human sacrifices at the site as an offering which they hoped might bring them better fortune, or simply to send out a powerful message to others in the area.

Some theories suggest communities made lavish burial displays because they felt under threat or were on the brink of significant change

“Viking burials and burying goods in graves is an ostentatious display,” he adds. “Burying something like a ship or a horse is an expensive thing to do and would have been an event that might last a week or more, so people could come and see it.

“But a human sacrifice would be taking things to another level.

“Presumably this was a burial of someone very important, or the community decided they needed this burial.”

According to Dr McLeod, there is no contemporary written evidence for human sacrifice taking place during the Viking conquest and settlement of Britain and Ireland.

The Herald: A collection of Viking treasure was found in 2014A collection of Viking treasure was found in 2014 (Image: PA)

However, a Viking grave in the Isle of Man has been found to point to human sacrifice. It was found to contain the remains of a man with a female’s remains on top, with evidence that a blow had sliced off the back of her skull.

The grave was topped with a layer of cremated animal bone – also thought to be a sacrifice.

But while the Whithorn grave and its cremation layer point to Viking presence, the reason why a human sacrifice may have taken place there remains shrouded in mystery.

One theory is that the sacrifice and cremation took place elsewhere and were brought to Whithorn for burial. Others that the site had been temporarily taken over by Scandinavians and the clergy had fled, or they were not able to prevent it happening.

“Regardless of the circumstances, if the cremated remains at Whithorn do represent human sacrifice, which is the most plausible explanation, then it is a clear example of non-Christian religious beliefs and burial rites there,” he adds.

“Along with the use of cremation, it is difficult to imagine a more overt form of non-Christian religious practice than human sacrifice.”

He added: “It was a violent era but the Vikings didn’t leave us any written records – they were carving runes, not writing things down

“With so much left to the imagination, it tends to make for great television programmes.”