Spoken by around 2,500 people in central Sweden, Elfdalian has been considered a dialect of Swedish, but recent research shows that it might be a distinct Nordic language.

In a book entitled A Grammar of Elfdalian, published by UCL Press in September, coauthors Yair Sapir and Olof Lundgren argue that Elfdalian is “a medieval language that survived up to modern times.” Using linguistic and archaeological evidence — including runes — the authors posit that Elfdalian is a descendant of Old Norse and developed in relative isolation. They conclude that the language has retained some unique features that set it apart from standard Swedish, such as the use of cases, and that significant differences from Swedish exist in terms of phonology, vocabulary, and grammar.

According to an article in The Guardian, runes were used in central Sweden longer than in other areas of the country and the world (as late as 1909). This provided researchers with evidence to date Elfdalian back to the last phase of ancient Nordic — spoken across Scandinavia between the sixth and eighth centuries. 

Sapir, a Senior Lecturer of Swedish Language at Kristianstad University, told The Guardian, “Research that compares the distance between Elfdalian [and Swedish] vocabulary [shows it] is as large as between Swedish and Icelandic. So there is higher mutual intelligibility between speakers of Swedish, Norwegian, and Danish than between Swedish and Elfdalian.”

In the book, the authors make the case for recognizing Elfdalian as an official language in Sweden in an effort to preserve and revitalize it for future generations. “If Elfdalian is recognized as a minority or regional language,” they write, “the number of speakers is likely to increase, and likewise the general level of Elfdalian language skills.”