1. “Norman”, which asserts that Rurik was a foreigner from Scandinavia and that it was he with his squad and retinue who formed the state of Russia from "unorganized" Slavic tribes. The Normans are a generalized name for the neighboring Scandinavian peoples in the Northern Baltic States – the Swedes, Danes and Norwegians, who ravaged Western Europe and Eastern Slavic lands with sea robber raids from the VIII to the XI century. Therefore, the "Norman" group is divided into three almost identical versions, which differ mainly by whether Rurik was a Swede, a Dane or a Norwegian.
The dashing "raiders" from across the sea were called either Vikings or Varangians. Some historians consider these words synonymous. Others believe that the Vikings are sea robbers who, unlike pirates, did not rob ships, but neighboring countries. They say that the Varangians were not robbers at all, but the defenders of their commercial business (for example, on the trade route "from the Varangians to the Greeks") or military mercenaries in various countries including in Byzantium and Russian principalities. The chronicle however says that it was the very Varangians, not the Vikings who raided and tried to impose tribute. So, there was a very fine line between Vikings and Varangians at that time.
2. "Slavic". That group of hypotheses claims that either Rurik was a Slav, just from an overseas tribe, or that Slavic statehood was formed long before the arrival of Rurik (if he ever arrived at all).
3. "Other Russia". The theories of the third group claim that there was some other strong and militant Varangian state "Rus", which was at war with almost every country around (including Byzantium) and was located not in Scandinavia, but somewhere else. This Russia subsequently merged with the Slavic lands, exerted its "civilizational" influence on the Slavic principalities, leading most of them, and gave the united state its name. Such versions are called either by the location of this "other" Russia, or by the people who inhabited it. The main theories of each group are briefly outlined below.