According to some modern ethnologists, ethnic Russians originated from the earlier Rus' people (East Slavs or Kievan Rus) and gradually evolved into a separate ethnicity from the western Rus peoples, who became known as the modern-day Belarusians and Ukrainians. Early ancestors of the Russians were East Slavic tribes migrating to the East European Plain in the early Middle Ages. Most prominent Slavic tribes in the area of what is now European Russia included Vyatichs, Krivichs, Radimichs, Severians and Ilmen Slavs. By the 11th century, East Slavs assimilated the Finno-Ugric tribes Merya and Muroma and the Baltic tribe Eastern Galindae that used to inhabit the same area with them (now Central Russia). Ethnic Russians (used to be) referred to as Great Russians (as opposed to the ethnonyms White Russian and Little Russian) and only began to be recognized as a distinct ethnic group in the 15th century. At that time, during the consolidation of the Russian Tsardom as a regional power, they were referred to as Moscovites. Between the 12th and 16th century, Russians known as Pomors migrated to Northern Russia and settled the White Sea coasts. As a result of these migrations and Russian conquests, following the liberation from the Mongol Golden Horde domination during the 15th and 16th century, Russians settled the Volga, Urals and Northern Caucasus regions. Between the 17th and 19th century, migrants settled eastwards in the vast, sparsely inhabited areas of Siberia and the Russian Far East. The Cossack movement played a significant role in these territorial expansions and migrations.     http://www.elkw.de/gemeinde_assets/3588.mp3