Great Russia

Great Russia, sometimes Great Rus', is a name formerly applied to the territories of "Russia proper", the land that formed the core of the Grand Duchy of Moscow and later the Tsardom of Russia. This was the land to which the ethnic Russians were native and where the ethnogenesis of Russians took place. The name is said to have come from the Greek Μεγάλη Ῥωσσία or Ῥωσία.
From 1654 to 1721, Russian Tsars adopted the word – their official title included the wording : "The Sovereign of all Rus': the Great, the Little, and the White".
The term is mentioned in the opening lines of the State Anthem of the Union of Soviet Socialist Republics: "Unbreakable Union of freeborn Republics Great Russia has welded forever to stand!".
Similarly, the terms Great Russian language and Great Russians were employed by ethnographers and linguists in the 19th century, but have since fallen out of use.
The area became, together with the Volga-Ural region, North Caucasus and Siberia became the Russian SFSR, while Little Russia and White Russia became the Ukrainian SSR and the Byelorussian SSR respectively.