Great Russia, sometimes Great Rus' (Russian: Великая Русь, Velikaya Rus', Великая Россия, Velikaya Rossiya, Великороссия, Velikorossiya), is a name formerly applied to the territories of "Russia proper", the land that formed the core of Muscovy and later Russia. This was the land to which the ethnic Russians were native and where the ethnogenesis of (Great) Russians took place. The name is said to have come from the Greek Μεγάλη Ῥωσ(σ)ία, Megálē Rhōs(s)ía used by Byzantines for the northern part of the lands of Rus'.