In the 9th language Old Norse speakers began their migrations through the whole Europe, started to be called Vikings, and therefore the language dialect varieties grew stronger until two separate languages appeared: Western Scandinavian, the ancestor of Norwegian, Icelandic and Faroese, and Eastern Scandinavian, the father-tongue of Danish and Swedish.
The most common features of the North Germanic and Old Norse languages were, for example, the passive vocie ending in -s, an enclitic form of the defonite article and some other.
Many Old Norse words were borrowed by English, Scots, nad even Russian,
due to vast scales of Viking migrations in the Middle Ages.