Russian Empire
Though the Empire was only officially proclaimed by Tsar Peter I following the Treaty of Nystad (1721), some historians would argue that it was truly born either when Ivan III of Russia conquered Veliky Novgorod in 1478, or when Ivan the Terrible conquered the Khanate of Kazan in 1552. According to another point of view, the term "Tsardom", which was used after the coronation of Ivan IV in 1547, was already a contemporary Russian word for empire.
Russians
Russian culture originated from that of the East Slavs, who were largely polytheists, and had a specific way of life in the wooded areas of Eastern and Northern Europe. The Scandinavian Vikings, or "Varangians", also took part in forming the Russian identity and state in the early Kievan Rus' period of the late 1st millennium AD. The Rus' accepted Christianity from the Byzantine Empire in 988, and this largely defined Russian culture for the next millennium, namely as a synthesis of Slavic and Byzantine cultures. After the fall of Constantinople in 1453, Russia remained the largest Orthodox nation in the world and claimed succession to the Byzantine legacy in the form of the Third Rome idea. At different points of its history, the country was strongly influenced by European culture, and since the reforms of Peter the Great Russian culture largely developed in the context of Western culture. For most of the 20th century, Marxist ideology shaped the culture of the Soviet Union, where Russia, i.e. the Russian SFSR, was the largest and leading part.