more conservative than towns. Legacy The Norse influence is considered to have left many traces on the Old East Slavic legal code, the Russkaja Pravda, and on literary works such as The Tale of Igor's Campaign, and even on the Byliny, which are old heroic tales about the early Kievan Rus (Vladimir the Great and others), where one of the words for "hero" is derived from Viking, i.e. (). Several scholars note that this is "of considerable importance generally, as far as social and cultural background of language is concerned". Although, they also note that parallels may arise from general similarities between Germanic and Slavic societies, they state that these similarities remain a profitable field of comparative studies. Russian contains several layers of Germanic loanwords that need to be separated from the North Germanic words that entered Old East Slavic during the Viking Age, Estimations of the number of loan words from Old Norse into Russian vary from author to author ranging from more than 100 words (Forssman) down to as low as 34 (Kiparsky) and 30 (Strumiński), including personal names. According to the most critical and conservative analysis, commonly used ON words include knut ("knout"), seledka ("herring"), šelk ("silk"), and jaščik ("box"), whereas varjag ("Varangian"), stjag ("flag") and vitjaz ("hero", from viking) mostly belong to historical novels. Many belong to a special field and ceased to be commonly used in the 13th c., such as berkovec (from ON *, i.e. "Birka/birk pound", referring to 164 kg), varjag, vitjaz, (from gulf meaning "box", "crate" or "shed"), grid, gridi (from griði, grimaðr meaning a "king's bodyguard"), lar (from *lári, lárr meaning "chest", "trunk"), pud (from pund referring to 16.38 kg), Rus (see etymology section above), skala (skál, "scale"), (thiónn, "Novgorod official" in the 12th c.), šelk (*silki, "silk"), and jabeda (embætti, "office"). Norse settlers also left many toponyms across North-Western Russia, where the names of settlements or nearby creeks reveal the name of the Norse settler, or where he came from. A man named Asviðr settled in a place today known as Ašvidovo, Bófastr in Buchvostovo, Dýrbjǫrn in Djurbenevo, Einarr in Inarevo, Kynríkr in Kondrikovo, Rødríkr in Redrikovo, Ragnheiðr in Rognedino, Snæbjǫrn in Sneberka, Sveinn in Sven', Siófastr in Suchvostovo, Steingrímr in Stegrimovo, and Thorbjǫrn in Turyborovo. More common Norse names have left several toponyms, such as Ivarr in Ivorovo and Ivorovka, Hákon in Jakunovo and Jakunicha, Oléf in Ulebovo, Olebino