The Tale of Sovius, which forms the basis of the 18th chapter of the Chronograph of 1262, raises questions about its own origin - oral or translated-written. It is sensible to carry out the discussion among folklorists and medievalists which sometimes resembles a dispute, on the basis of comparative textology.
In order to substantiate the authenticity of the text and its folkloric features, it is useful to describe as many storyline parallels as possible. The view of Jiří Polívka's Prague Geographical-Historical School encourages us first of all to survey the region of North-Eastern Europe.
In East Slavic folklore we can find two texts comparable to the Tale of Sovius. They are both closely interconnected.
One of them is attested in the 12th century annals "The Tale of Bygone Years" (945-946), but it derives from an older collection of annals (Nachal'nyi Svod) dating back to the ninth decade of the 11th century. This collection is made of elementary folklore storylines traditionally called "Duchess Olga's Revenge on Drevlians for Her Husband's Murder." The other text is an epic song about the hero Mikhail Potyk.
A comparative analysis of the bylina and the narrative in the annals shows that East Slavs once had a related work of a similar structure and semantics. The fact that the folklore work was recorded in the annals reveals an important circumstance - the narrative was so well-known and relevant that after it had penetrated into a literary medium, it had a significant impact on the formation of the historiographical genre in Kievan Rus' and the Grand Duchy of Lithuania.
The narrative, widespread in the East Slavic territory, related a story about the character's encounter with an antagonist (possessing characteristics of a witch or some other mythical being) who tried three times in a row to get rid of the character: the character is buried into the earth, cremated and killed/buried on a tree.