The first English prose version of the Arthurian legend was penned by Sir Thomas Malory, a knight of uncertain identity who is thought to have turned to a life of crime during England’s Wars of the Roses. Parts of Malory’s tale, which he finished while in prison, were based on a group of 13th-century French romances known as the Vulgate Cycle.

Now, as Steven Morris reports for the Guardian, scholars in the U.K. have announced the discovery of seven manuscript fragments that appear to belong to this Old French sequence—though the texts differ in small but significant ways from known versions of the cycle.

Michael Richardson, a special collections librarian at the University of Bristol, found the texts by accident, while looking for material to show graduate students in a Medieval Studies program. He was examining fragments that had been used in the binding of a four-volume work by the 14th-century French scholar Jean Gerson when a word jumped out at him: “Merlin.”

Richardson quickly got in touch with Leah Tether, a scholar of medieval French literature and Arthurian romance at the University of Bristol, who instantly recognized the texts as belonging to the Vulgate Cycle.

“As soon as I opened them, I could immediately see that the fragments were early, in terms of Arthurian narrative,” she tells Australia’s ABC News. “Bearing in mind that most of the Old French versions of the legend were written in the early 13th century, this manuscript is quite close in time to those original compositions.”

The books in which Richardson spotted the fragments were printed in Strasbourg at some point between 1494 and 1502. According to the University of Bristol, these copies appear to have been bound in England in the 16th century. Tether and her colleagues believe the Arthurian fragments were scraps that had been lying around the binder’s workshop that were stuffed into the binding as a cost-saving measure. It wasn’t unusual for book binders of centuries past to recycle old “waste material,” rather than use fresh sheets of expensive parchment.

Damage to the fragments suggests they were originally pasted onto the boards at the front and back of the books—boards that “connect the pages to the binding,” according to the university. But at some point, the fragments seem to have been peeled back and repurposed as flyleafs, or the blank pages at a book’s front and back cover.

This caused significant damage to the texts, but parts of them are still readable. Scholars were able to determine that they come from the Estoire de Merlin, a sequence that focuses on a battle pitting Arthur, Merlin, Gawain and other knights against their rival, King Claudas. The narrative includes a long description of the fight, at the center of which is Merlin, who bolsters Arthur’s troops with a rallying speech, and then leads the charge bearing a magical dragon standard that breathes real fire.

When examining the texts, Tether and her colleagues noticed several differences between this version and others that are known to exist. King Claudas, for instance, is typically depicted as being wounded in the thigh, but these fragments do not specify the nature of his injury. Additionally, in the newly discovered narrative, the characters placed in charge of leading Arthurs’ troops are different from the ones assigned to the task in the established version of the legend.

These aren’t major distinctions, but they have prompted scholars to wonder how the fragments might have influenced later tellings—particularly Malory’s famed account of the escapades of King Arthur and Co.

“We know he used a version of this French text as a source for his version of the legend, but nobody has yet identified which version,” Tether explains in her interview with ABC News. “No known [version] that exists is what he used—[they’re] not identical with what he wrote about.”

Experts are now working to fully decipher the contents of the fragments, which might help them match the narrative to later renditions of the Arthurian legend. Speaking to ABC, Tether says the possibility of there being a connection between the new texts and Malory’s narrative is “small, but tantalizing.” And even if no connection exists, this is an exciting find for experts in the field. The discovery of Arthurian fragments—and particularly the discovery of Old French fragments in England—is a rare occurrence, Tether tells ABC.

“To me it feels like a once-in-a-lifetime find,” she says. “You just don’t get quite that many of these popping up.”