The secret science behind the Viking supersword “Ulfberht”

Researchers have uncovered approximately 170 of these Viking superswords. They date from 800 to 1,000 A.D. and are all inscribed with a single word – “Ulfberht”, which some believe is linked to the identity of their maker – and two crosses.

One of the most perplexing things about the Ulfberhts is the strength of the metal from which they were made. The material, known as “crucible steel”, is so strong and pure that it seems inconceivable that any blacksmith of that time could have handled it. In fact, since the age of the Ulfberht, this quality of steel was not seen again in Europe for over a thousand years. However, at the time the Ulfberht swords were being forged, similar weapons were also being produced in the Middle East. The latter were made of so-called “Damascus steel”, which comes from a raw material known as Wootz steel, and originates in Asia. Both Damascus steel and crucible steel have been found to contain unusually high amounts of carbon.

The experiment was a success. However, although Furrer was satisfied that it would have been possible to build a sword of this quality in the Viking age, he remained puzzled as to how the Vikings got hold of the steel. “The biggest mystery is where did they get this raw material,” Furrer told Nova. “We have no evidence of crucible steel production in Europe until 800 years later.” According to Fredrik Charpentier Ljungqvist, a researcher at Stockholm University, the answer may be quite simple. The existence of the Damascus swords prove that, while the expertise to create crucible steel did not yet exist in Europe, it was present in the Middle East. Meanwhile, artifacts found at archeological sites from the Viking era prove that the Medieval Norsemen traded with the East. We also know that they could travel by water – on rivers and lakes – all the way from Lake Mälaren outside modern-day Stockholm to northern Iran. The route was known as the Volga trade route.

“Most Ulfberht swords are dated from the exact same time that the Volga trade route was open,” Charpentier Ljungqvist told Nova. “I think it’s very likely that the steel found in Ulfberht swords originated in Iran. I would guess that you bought it from friendly trading connections in Iran, paid with furs or other Nordic commodities, and took it back on your small ships that you used on rivers.” Dr. Alan Williams of the Wallace Collection in London is one of the world’s leading experts on historic steel weaponry. Williams agrees with Charpentier Ljungqvist: “After the 11th century, the Volga trade route is closed and the manufacture of these Ulfberht swords stops, which to me is strong evidence that they were made out of an imported raw material,” he explained.

While Ulfberht is a Frankish name, the cross was a symbol typically only used by high-ranking members of the Roman Catholic Church, such as bishops or abbots. Although the Catholic Church was an enemy of the pagan Vikings, it was a major producer and dealer of arms. But if the swords were made by Catholics and smuggled North to their sworn enemies, how did the church get the steel? The theory that the Vikings brought it from the Middle East would appear to make more sense. Dr. Williams believes there are many reasons why a Scandinavian might have used a foreign word and the cross. “It might have been magic, it might have been copying symbols from the disappeared Roman Empire, it might have been simply because someone thought they liked the name, like putting the name Apple on a computer,” he admitted to Nova.