Calling all codebreakers. The British Library has appealed to members of the public to help decipher an inscription found on an 800-year-old sword which has left experts stumped.

The double-edged steel blade, which was found in the River Witham near Lincoln, England in the 19th century, is a finely crafted model which is likely to have been very expensive and probably belonged to a wealthy man or a knight, CNET reported.

Experts also claim that the weight of the weapon could split a human skull in two if handled by a skilled swordsman.

Experts aren’t sure what the sword’s mysterious inscription means.
Photo: British Library via CNET

But what library staff can’t explain is the mysterious inscription engraved onto the sword which reads: +NDXOXCHWDRGHDXORVI+

“An intriguing feature of this sword is an as yet indecipherable inscription, found along one of its edges and inlaid in gold wire,” Curator Julian Harrison wrote on the British Library’s blog.

“It has been speculated that this is a religious invocation, since the language is unknown.”

Marc van Hasselt of Utrecht University, Netherlands has studied dozens of similar weapons. He says personalizations such as inscriptions were “all the rage” in 13th century medieval Europe. “Looking at the other European finds, it seems most likely that this language is Latin,” he explained

The sword is on view at the British Library until September 1.
Photo: http://magnacarta800th.com

“On the River Witham sword, it is NDXOX, possibly standing for Nostrum Dominus (our Lord) or Nomine Domini (name of the Lord) followed by XOX…Perhaps these letter combinations—XOX and OXO—refer to the Holy Trinity.”

Another theory put forward by readers commenting on Harrison’s blog post also suggested that the inscription could be acronyms.

The Sword is part of the Magna Carta: Law, Liberty, Legacy exhibition; which is on view at the British Library until September 1.

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